The second purpose of baptism is so that a Christian may get to know and acknowledge the Lord Jesus Christ, the Redeemer and Saviour, and follow him.
This second purpose of baptism, which is getting to know the Lord, the Redeemer and Saviour Jesus Christ, comes as the inseparable companion of the first, which is being brought into the Christian church and being associated with Christians in the spiritual world. What would that first purpose be, without this second one to follow it, but a mere name? Yet it would be like a subject who swears allegiance to a king, but then rejects the king's or his country's laws, and swears allegiance to and serves a barbarian king. Or it would be like a servant who goes into service with a master and takes his clothing to wear as a livery, and then runs away and serves another master while still wearing the livery of his former master. Or he would be like a standard-bearer who goes off with the colours, cuts them in pieces and throws them to the winds or to be trampled under the soldiers' feet. In short, his name of Christian, that is, of belonging to Christ, without acknowledging Him and following Him, that is, living in accordance with His commandments, is as meaningless as a shadow, smoke or a blacked-out painting. For the Lord says:
Why do you call me Lord, and not do what I tell you? Luke 6:46ff.
Many will say to me on that day, Lord, Lord. But then I shall admit to them, I do not know you. Matt. 7:22, 23.