"In those days came John the Baptist, who preached in the wilderness of Judea and said : Repent, for the kingdom of heaven has come near." Matthew 3: 1, 2
John the Baptist announces the prophet who spoke: the long awaited Messiah who, for all Jews, was to deliver Israel from Roman colonization. At that time, the Pharisees watched over the respect of ritual purity. Thus, the faithful had to respect the 613 prescriptions that rabbinical tradition had derived from the Law : not to eat with strangers, to abstain from foods declared unclean, and so on. We were defiled by the lack of vigilance and we had to purify ourselves. Originally, the purpose of the Law was to distinguish the chosen people from other nations, to avoid falling into the trap of idolatry.
The message of John the Baptist surprises: he speaks of repentance, which presupposes a new attitude, a change in depth. His baptism no longer refers to the superficial purification of a particular fault. It is the sign of the consecration of a person who wants to submit to the authority of God.
Jesus will explain this need to his disciples : "It is from the heart that evil thoughts come ... that is what defiles man ; But to eat with unwashed hands does not defile the man" (Matthew 19:20). Clearly, evil no longer comes from the outside but from the heart. Moreover, on seeing Jesus, John the Baptist exclaims, "This is the Lamb of God who takes away the sin of the world" (John 1:29). Already the prophet Isaiah had mysteriously alluded to this long-awaited Servant who was presented as the Lamb of God "... he was bruised for our iniquities ... and by his wounds we are healed" (Isa.55: 5).
These words radically change the conditions to be accepted by God.
For many Jews of the time, it was a question of observing a rite of atonement without the heart being engaged. The apostle Peter, a convinced Jew, took time to understand that these practices of worship were shadows. But he declares to scattered believers, "... you have been redeemed from your vain conduct, which you were taught by your fathers ... through the precious blood of Christ" (1 Pet. 1:18, 19). Today we are invited to offer the sacrifices that the Spirit produces in us to the glory of God the Father and his glorified Son.
Source (To pleasing the Lord)