Biblical Commentary
(Bible study)

Luke 3:15-17, 21-22




The Holy Spirit is mentioned in both halves of our Gospel lesson. In the first half, John says that the one who is coming “will baptize you in the Holy Spirit and fire” (v. 16). In the second half, Jesus is baptized, “and the Holy Spirit descended in a bodily form as a dove on him” (v. 22). In between (not included in this Gospel lesson) is the story of John’s arrest.

The Holy Spirit is important to Luke, and we find references to the Holy Spirit throughout Luke-Acts (both written by Luke). Even in the very earliest chapters of Luke, there are several mentions of the Holy Spirit:

• In the announcement of John’s birth, the angel tells Zechariah that John “will be filled with the Holy Spirit” (1:15).

• In the announcement of Jesus’ birth, the angel tells Mary, “The Holy Spirit will come on you” (1:35).

• Elizabeth, “filled with the Holy Spirit,” sings Mary’s praises (1:41-45).

• Simeon “came in the Spirit” to see and praise Jesus in the temple (2:27-32).

• See also Luke 4:1, 18; 10:21; 11:13; 12:10, 12 and Acts 1:5; 2:1-4, 17, 38; 4:8, 25, 31; 5:3, 32; 6:5; 7:51, 55; 8:15-19, 29, 39; 9:17, 31; 10:19, 38, 44-48; 11:12, 15, 24; 13:2, 4, 9, 52; 15:8, 28; 16:6-7; 19:1-17; 20:22-23, 28; 21:4, 11; 28:25.

The beginning verses of chapter 3 echo Luke’s introduction of Jesus’ birth story of chapter 2—”Now in the fifteenth year of the reign of Tiberius Caesar, Pontius Pilate being governor of Judea” (3:1)—except that this time Luke is introducing the work of John the Baptist (3:2-20) and the baptism of Jesus (vv. 21-22). It is just Luke, the historian, once again carefully setting Jesus in historical context.

The ministry of John the Baptist and the baptism of Jesus are inextricably linked. John bears witness to Jesus and baptizes him—except that Luke does not tell us that John performed the baptism, but says only “Jesus also had been baptized” (3:21)—we have to rely on Mark 1:9 and Matthew 3:13-15 to learn that it was John who performed the baptism. Luke’s decision not to mention John’s name in connection with Jesus’ baptism is one of the several ways that he subordinates John to Jesus.

All four Gospels are careful to subordinate John to Jesus—making it clear that John is not the Messiah, but is only preparing the way for the Messiah. Luke takes the additional step of inserting the story of John’s arrest (vv. 18-19) just before his account of Jesus’ baptism (vv. 21-22)—thus ending John’s ministry just as Jesus’ ministry begins. Mark and Matthew tell of John’s arrest and death much later in their accounts (Mark 6:14-29; Matthew 14:1-12).

In each of the Synoptics, Jesus’ temptation follows his baptism. Mark and Matthew place the temptation immediately after the baptism, but Luke interjects Jesus’ genealogy between the baptism and temptation (3:23-38).


15As the people were in expectation, and all men reasoned in their hearts concerning John, whether perhaps he was the Christ, 16John answered them all, “I indeed baptize you with water, but he comes who is mightier than I, the latchet of whose sandals I am not worthy to loosen. He will baptize you in the Holy Spirit (pneumati hagio) and fire, 17whose fan is in his hand, and he will thoroughly cleanse his threshing floor, and will gather the wheat into his barn; but he will burn up the chaff with unquenchable fire.”

and all men reasoned in their hearts concerning John, whether perhaps he was the Christ” (v. 15). The Jews have experienced centuries of prophetless years. Now John’s ministry brings the kind of spiritual intensity that they have known previously only by reading long-dead prophets. It is no wonder that they think that John might be the promised one—the messiah.

“John answered them all” (v. 16a). John distinguishes himself from Jesus in three ways:

1. I indeed baptize you with water, but he comes who is mightier than I, the latchet of whose sandals I am not worthy to loosen” (v. 16b). Jesus is more powerful and of infinitely higher status. John is not worthy to tie his sandals, a task so demeaning that Jewish slaves are exempted from performing it. Today, John might say, “I am not worthy to carry his bags”—or “I am not worthy to carry out his garbage.”

2. He will baptize you in the Holy Spirit (pneumati hagio) and fire” (v. 16c). John baptizes with water, but Jesus baptizes with the Holy Spirit (pneumati hagio) and fire.

The Greek word, baptizo, has to do with being overwhelmed or immersed. John is not talking here about Jesus performing water baptism, but is instead talking about Jesus overwhelming us—immersing us—in the Holy Spirit and fire. “John baptizes with water—an outward symbol; the Messiah’s Spirit baptism is the reality to which the symbol points” (Wright, 316).

We derive our word, “pneumatic,” which we use for air-powered tools, from the Greek word, pneumati. Pneumati can be translated either spirit or wind, and it is very possible that Luke intends the ambiguity—intends us to think both of spirit and wind.

• When introducing the story of Pentecost, Luke will speak of all three—wind (pnoes—Acts 2:2), fire (puros—Acts 2:3), and Holy Spirit (pneumatos hagiou—Acts 2:4)—in the space of three short verses.

• In the winnowing fork metaphor (v. 17), wind separates chaff from wheat (although Luke does not use the word pneumati in v. 17), and fire destroys the chaff. In this Gospel, Jesus and the disciples several times use fire as a metaphor for judgment (9:54; 12:49; 17:29). Wind and fire are both instruments of judgment, but the purpose is to “preserve what is valuable and (to) destroy what is worthless, just as a farmer does” (Tannehill, 82). They are like the refiner’s fire, which purges dross to purify silver and gold (Isaiah 1:25; Zechariah 13:9; Malachi 3:2). The aim is not destruction, but purification.

3. whose fan is in his hand, and he will thoroughly cleanse his threshing floor, and will gather the wheat into his barn” (v. 17a). A winnowing fork is somewhat like a pitchfork. It is used to toss grain into the air so that the wind will carry away the lighter chaff and allow the heavier, more valuable grain to fall back to the floor. Winnowing is a way of separating that which is worthless (the chaff) from that which is valuable (the grain). Winnowing thus serves as a metaphor for Jesus separating the faithful from the unfaithful—the saved from the lost—on Judgment Day.

he will thoroughly cleanse his threshing floor, and will gather the wheat into his barn” (v. 17b). A threshing floor is a large, hard-packed surface where oxen pull a heavy sled over sheaves of wheat to pull the chaff away from the grain, preparing it for the winnowing fork.

After the grain is collected on the threshing floor, it is gathered into a granary or storage area where it will be protected from the weather. Winnowing separates the useful grain from useless chaff by using a winnowing fork to throw the wheat and chaff into the air when a breeze is blowing. The heavier wheat will be little affected by the breeze, but the lighter chaff will be blown away from the threshing floor. This separation of good (wheat) from bad (chaff) serves as a metaphor for Jesus separating the redeemed from the unredeemed—and gathering the redeemed into their heavenly home.

The “unquenchable fire” (v. 17b) serves as a metaphor for the eternal punishment of those who are not redeemed, and thus speaks of the eternal consequences of our choices. Jesus has authority to burn the chaff with unquenchable fire. He is not just a prophet, announcing consequences, but is also a judge, imposing consequences.

Isaiah used similar language to describe the fate of people who rebelled against God (Isaiah 66:24—see also Mark 9:48). “Unquenchable fire” brings to mind Gehenna—the Valley of Hinnom—Jerusalem’s garbage dump, where fires burn day and night.

While a frightful image, the chaff-burning does not celebrate the sinner’s demise. John called sinners to “bear fruits worthy of repentance” (3:8). Those who do so will be identified as wheat rather than chaff, and will thus be saved. This story thus highlights both salvation and judgment (condemnation), but the purpose is “to save the wheat, not to burn the chaff” (Craddock, Interpretation, 49).


The lectionary excludes these verses—the story of John’s arrest—thus pulling together John’s testimony about the baptism that Jesus offers (v. 16) and the baptism that Jesus receives (v. 21). As noted above, Mark and Matthew tell of John’s arrest and death much later in their accounts (Mark 6:14-29; Matthew 14:1-12). If Luke’s chronology were correct, John could not have baptized Jesus, because he would have been in prison when Jesus was baptized. Luke places the arrest early as another way of emphasizing John’s subordinate role.

The story of John’s arrest reminds us that discipleship is no bed of roses. John will be Jesus’ forerunner, not only in life and ministry, but also in death.


21Now it happened, when all the people were baptized, Jesus also had been baptized, and was praying. The sky was opened, 22and the Holy Spirit descended in a bodily form as a dove on him; and a voice came out of the sky, saying “You are my beloved Son. In you I am well pleased.”

Luke’s account of Jesus’ baptism is very spare—”relegates mention of Jesus’ baptism to a dependent clause, almost an aside…. The primary focus…is on the descent of the Holy Spirit and the heavenly voice” (Nickle, 36).

“when all the people were baptized” (v. 21a). This statement signals the closure of John’s ministry. John has been the forerunner of Jesus all of his life, but now it is time for Jesus to occupy center stage.

Jesus also had been baptized, and was praying. The sky was opened” (v. 21b). Luke does not describe the baptism itself—does not mention John—does not say that Jesus came up out of the water (Mark 1:10; Matthew 3:16)—does not tell us that Jesus was baptized to fulfill all righteousness (Matthew 3:15). Luke’s concern is elsewhere—with the endorsement implied by the opened heaven, the descent of the Holy Spirit, and the voice from heaven. This is Jesus’ anointing—his preparation for service—his empowerment.

Heaven opens, not at Jesus’ baptism, but during his prayer following his baptism. Prayer is important for Luke, who frequently portrays Jesus at prayer (5:16; 6:12; 9:18, 28-29; 11:1; 22:32, 41-45; 23:34, 46) or encouraging his disciples to pray (6:28; 18:1; 22:40, 46). He also portrays the church at prayer (Acts 1:14; 6:4; 8:24; 10:9; 14:23; 16:13, 16; 26:29). Is it too much to say that Jesus’ ministry and the ministry of the church are prayer-powered? However we choose to phrase it, Jesus’ prayer life and that of the early church serve as a model—encourage us to find strength in the same place that they found it.

Heaven opens so that the voice can be heard and the Spirit can descend. The opening of heaven is an apocalyptic motif that announces the presence and intervention of God (see Ezekiel 1:1; Isaiah 64:1; John 1:51; Acts 7:56; Revelation 19:11). It signals that Jesus has come as messiah.

John baptizes for repentance (3:11). Jesus is the uniquely sinless one who needs no repentance, so we wonder why he chose to be baptized. Scholars have advanced a number of possibilities—none conclusive—perhaps all true to some degree:

• Matthew tells us that Jesus was baptized to fulfill all righteousness (Matthew 3:15), implying that God ordained that Jesus should be baptized and that Jesus is complying with God’s will. That, however, fails to explain why God ordained the baptism. We are left with the original question—Why? Besides that, Luke does not include this comment about righteousness, so it would not be his explanation for the baptism.

• Jesus’ baptism constitutes an endorsement of John’s ministry and recognition of John’s baptism “as a preparatory stage of (Jesus’) own ministry” (Fitzmyer, 482).

• Jesus’ baptism marks the turning point. The important part of John’s ministry has been accomplished, and he will begin to fade into the background. Jesus’ baptism initiates the beginning of his ministry (Culpepper, 90).

• Baptism is a gift—a process by which God dispenses grace—and Jesus chooses to receive the gift.

• Jesus is setting an example for his disciples, encouraging their baptism when the right time comes.

and the Holy Spirit descended in a bodily form as a dove on him” (v. 22). This is Jesus’ anointing, which sets him apart for his unique ministry.

Luke told us earlier that Jesus was conceived by the Holy Spirit and that Mary’s child would thus be holy (1:35). He told us that John, Elizabeth, Zechariah, and Simeon were filled with the Holy Spirit (1:15, 41, 16; 2:25-27) and that Jesus grew in spirit (1:80), but he has not yet told us that Jesus was filled with the Holy Spirit or that the Spirit rested on him. It would appear, then, that the descent of the Spirit at Jesus’ baptism is a new and necessary empowerment for ministry.

In chapter 4, Jesus will tell us the nature of his ministry:

“The Spirit of the Lord is on me,
because he has anointed me to preach good news to the poor.
He has sent me to heal the brokenhearted,
to proclaim release to the captives,
recovering of sight to the blind,
to deliver those who are crushed,
and to proclaim the acceptable year of the Lord”

After Jesus’ baptism, Luke mentions several times that Jesus is filled with—or led by or empowered by the Spirit (4:1, 14, 18)—or that he rejoices in the Spirit (10:21). He tells his disciples that they can expect to receive or to be guided by the Holy Spirit (11:23; 12:12; Acts 1:5, 8). He relates many instances of the fulfillment of that promise (Acts 2:4, 33; 4:8, 31; 6:3-5, 10; 7:55; 8:17-18, 29; 9:17, 31; 10:19, 44-47; 11:12, 15-16, 24; 13:2, 4, 9, 52; 15:8; 16:6-7; 19:6; 20:22-23; 21:4).

“in a bodily form as a dove on him” (v. 22b). The Spirit is visible—no figment of anyone’s imagination. The Spirit is not a dove, but is like a dove. There is no mention in the Old Testament of the Holy Spirit descending like a dove. The dove that appeared to Noah as the floodwaters receded (Genesis 8:8) is the best-known Old Testament dove, and perhaps the most helpful to understand the dove-like Spirit at Jesus’ baptism. The Genesis dove was a peaceful symbol—a sign of God’s presence—a promise of salvation. The same is true for the dove-like Spirit at Jesus’ baptism.

and a voice came out of the sky, saying ‘You are my beloved Son. In you I am well pleased'” (v. 22c). Luke doesn’t identify the one who speaks, but the voice from heaven is obviously that of God the Heavenly Father.

These are essentially the same words that God will speak at the transfiguration (9:35), except that they are addressed to Jesus at his baptism—but to the disciples at his transfiguration. Verse 22 alludes to two Old Testament verses, “You are my son” (Psalm 2:7) and “my chosen, in whom my soul delights” (Isaiah 42:1).

Jesus does not become God’s son at his baptism, but has been God’s son all along (1:35). Son of God is far superior to son of Abraham. John warned the people that their claim to Abraham as their ancestor would avail them nothing, and that they were, in fact, sons of vipers (3:7-8).

SCRIPTURE QUOTATIONS are from the World English Bible (WEB), a public domain (no copyright) modern English translation of the Holy Bible. The World English Bible is based on the American Standard Version (ASV) of the Bible, the Biblia Hebraica Stutgartensa Old Testament, and the Greek Majority Text New Testament. The ASV, which is also in the public domain due to expired copyrights, was a very good translation, but included many archaic words (hast, shineth, etc.), which the WEB has updated.


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Craddock, Fred B.; Hayes, John H.; Holliday, Carl R.; and Tucker, Gene M., Preaching Through the Christian Year, C (Valley Forge: Trinity Press, 1994)

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Copyright 2010, 2012, Richard Niell Donovan