John the Baptist was a servant of God, who was born 6 months prior to Jesus, and was foretold in Malachi, would be the last Prophet in the Old Testament.
“Remember the Law of Moses, My servant, which I commanded him in Horeb for all Israel, with the statutes and judgments. Behold, I will send you Elijah the prophet before the coming of the great and dreadful day of the Lord. And he will turn the hearts of the fathers to the children, and the hearts of the children to their fathers, lest I come and strike the earth with a curse” (Malachi 4:4-6).
When Jesus was born, the people of Israel abandoned the words of God’s Covenant and worshipped foreign gods. They offered the blind and blemished animals as sacrifices, and made the temple of God a place of business. Jesus Christ, too, is foretold in the Law of Moses and the Prophets. The Law gives humanity the knowledge of sin, showing how they are sinful (Romans 3:20). It is a sin not to abide by a single commandment written in the books of the Law.
In the Old Testament, a sinner who disobeyed any of the articles of the Law brought a sin offering in front of the tabernacle, put his hand on the head of the sin offering to pass his sin onto it, and killed the sin offering to be forgiven for the sin and be united with God again. Then, the priest took some of its blood and put it on the horns of the altar of burnt offering and poured out all the rest of its blood at the base of the altar.
However, the people of Israel couldn’t be delivered from all their sins, regardless of their countless daily offerings. Therefore, God made a permanent statute for them, the Day of Atonement. It was at this time God would forgive their yearly sins on the tenth day of the seventh month. On that day Aaron, the High Priest, took two goats and cast lots for them; one for the Lord and the other for the scapegoat. Then, he laid his hands on the head of the goat for the Lord to lay all the yearly sins of the people of Israel on it. Aaron then slew it and took its blood to sprinkle it seven times on and in front of the mercy seat.
When he finished atoning for the Holy Place, he offered the other animal. He laid his hands on the head of the live goat and confessed over it all the yearly sins of the Israelites. By this method, all their yearly sins were passed onto it, and it was sent away into the wilderness by the hand of a suitable man. The Israelites were redeemed from their yearly sins in this way.
However, the sacrifice offered according to the Law of the Old Testament could not make those, who offered sacrifices continually year-by-year, perfect. It was merely a shadow of the good things (the righteous acts of Messiah) to come (Hebrews 10:1). People of Israel did not wait for Jesus Christ, the Savior. Instead, they worshipped the foreign gods of the sinful world, abandoning the words of the Prophets in the Old Testament.
Thus, God foretold that He would send John the Baptist in order to restore the hearts of the Israelites, to return them to Him, and to prepare their hearts to receive Jesus Christ. Before John the Baptist baptized Jesus, he gave the baptism of repentance to the people of Israel in the wilderness of Judea.
His purpose of baptizing them with water was to lead them to wait for and believe in Jesus. He taught that the Savior would be baptized by him in the way of the laying on of hands to take away all the sins of the world, and then crucified to save them from all their sins. He said that Jesus would come and take away the incomplete sacrifices of the past and offer the eternal sacrifice with His body; He would take all our sins through the baptism, just as the people of Israel were redeemed by bringing a sin offering without blemish, laying their hands on it, and slaying it according to the sacrificial system in the Old Testament.
Many Israelites confessed their sins, repented, and were baptized by him. “Repentance” means “to return one’s mind to the Lord.” Remembering the Law of the Old Testament, they came to John and confessed that they were hopeless sinners who could not but commit sins until they died. They also confessed that they could not enter the Kingdom of Heaven with their good deeds according to the Law, and returned their minds to Jesus Christ, who would blot out all their sins once and for all, opening the gate to the Kingdom of Heaven.
The baptism that John the Baptist gave to the people of Israel was the following. He let them confess how much they sinned in their lives, repented and looked for Jesus Christ, who would be baptized by him, the High Priest and representative of all humankind, and crucified to save them from all their sins, just as he baptized them. This is a true biblical repentance.
Therefore, John exclaimed to the people, “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” (Matthew 3:11).
John the Baptist turned peoples’ minds to Jesus, testified to them that Jesus would take away all the sins of the world (John 1:29) and die for them vicariously. Thus, Jesus Himself bore witness that John came to show us the way of righteousness (Matthew 21:32).