John the Baptist baptised with water, but he said that One mightier than him (Jesus Christ) would baptise with the Holy Spirit and fire.

What is this baptism with fire?  Is it receiving the Holy Spirit with “tongues of fire” as in the day of Pentecost?  Is it enduring some fiery trial, of which Shadrach, Meshach, and Abed-Nego’s experience was a type?  Or is it being thrown into the lake of fire and brimstone?

Baptism with fire is mentioned in only two verses, Matthew 3:11 and Luke 3:16.  The surrounding passages are similar, so we need only look at one of them to get the context to understand what is “baptism with fire”.

Mat 3:1  In those days John the Baptist came preaching in the wilderness of Judea,
Mat 3:2  and saying, “Repent, for the kingdom of heaven is at hand!”
Mat 3:3  For this is he who was spoken of by the prophet Isaiah, saying: “THE VOICE OF ONE CRYING IN THE WILDERNESS: ‘PREPARE THE WAY OF THE LORD; MAKE HIS PATHS STRAIGHT.’ “
Mat 3:4  Now John himself was clothed in camel’s hair, with a leather belt around his waist; and his food was locusts and wild honey.

John the Baptist preached repentance.  He warned people to stop sinning.

Mat 3:5  Then Jerusalem, all Judea, and all the region around the Jordan went out to him
Mat 3:6  and were baptized by him in the Jordan, confessing their sins.

Many people in the region of Judea confessed their sins.

Mat 3:7  But when he saw many of the Pharisees and Sadducees coming to his baptism, he said to them, “Brood of vipers! Who warned you to flee from the wrath to come?
Mat 3:8  Therefore bear fruits worthy of repentance,

John warned the Pharisees and Sadducees, the religious leaders, to bear fruits worthy of repentance.  In other words, to genuinely repent, and show some change in behaviour.

Mat 3:9  and do not think to say to yourselves, ‘We have Abraham as our father.’ For I say to you that God is able to raise up children to Abraham from these stones.
Mat 3:10  And even now the ax is laid to the root of the trees. Therefore every tree which does not bear good fruit is cut down and thrown into the fire.

It seems that the Pharisees and Sadducees were relying on being descendants of Abraham to save them.  Fruit trees that do not bear good fruit are chopped down and burned.  The implication is that those who do not show the fruits of repentance will be destroyed with fire.

Mat 3:11  I indeed baptize you with water unto repentance, but He who is coming after me is mightier than I, whose sandals I am not worthy to carry. He will baptize you with the Holy Spirit and fire.
Mat 3:12  His winnowing fan is in His hand, and He will thoroughly clean out His threshing floor, and gather His wheat into the barn; but He will burn up the chaff with unquenchable fire.”

There are two possible outcomes: being preserved or being burned up.  The wheat (the good fruit) is preserved in the barn, and the rubbish (the bad fruit) is burned.  See “What does ‘their worm does not die and the fire is not quenched ‘ mean?” for more information on the unquenchable fire.  The two baptisms mentioned must surely agree with these two possible outcomes.  Baptism with the Holy Spirit we know leads to eternal life—preservation.  Baptism with fire must therefore correspond with the second outcome—being burned up. 

When the context of the passage is considered the most compelling meaning of “baptism with fire” is being burned up—being thrown into the lake of fire and brimstone.