As part of our mid-week bible study, we have been discussing John the Baptist and how he prepared the way for Christ. I understand John's mission and the importance of baptism, but was it also used to prepare the people for the conversion (burial) into Christ? What was the significance of baptism by John and his teachings?
John's baptism of the people is the first mention of baptism in the Bible. Water was used in the Old Testament for ceremonial cleansing to remove uncleanness (Numbers 19:7), but there is no mention of complete immersion, particularly in connection with the removal of sin. Some have claimed that John was extending an old custom from the ancient days of Israel, but such is not found in the Bible. That baptism was a new rite is shown by the Jews’ question of John, “Why then do you baptize if you are not the Christ, nor Elijah, nor the Prophet?” (John 1:25). They questioned his right to add a new ordinance if he did not have sufficient authority. They understood that ordinary men cannot change the practices authorized by God.
John's purpose was to prepare people for the coming Christ (Matthew 11:10). Paul explained, "John indeed baptized with a baptism of repentance, saying to the people that they should believe on Him who would come after him, that is, on Christ Jesus" (Acts 19:4). It wasn't the same as Christ's baptism. We see this in Ephesus because after Paul explained the difference, the men in Ephesus were baptized again, this time into Christ (Acts 19:5).
Still, I believe you are right that John's work did get Israel ready for Christ's baptism by experiencing a similar rite.
We recently studied John as a part of a series of lessons going through the Gospels. There is material on the nature and purpose of John's preaching in the lesson "John's Ministry."