The third purpose of baptism, which is its end in view, is a person's regeneration.
This is the real purpose behind baptism, and so the end with a view to which it was instituted. The reason is that one who is truly a Christian gets to know and acknowledge the Lord the Redeemer, Jesus Christ; and since He is the Redeemer, He is also the Regenerator. Redemption and regeneration are one; see section III [579-582] in the chapter on reformation and regeneration. Another reason is that a Christian possesses the Word, in which is available a description of the means of regeneration, and these are faith in the Lord and charity towards the neighbour. This is the same as when it is said of the Lord that He will baptise with the Holy Spirit and with fire (Matt. 3:11; Mark 1:8-11; Luke 3:16; John 1:33). The Holy Spirit means the Divine truth of faith, fire the Divine good of love or charity, both of these proceeding from the Lord. For the Holy Spirit meaning the Divine truth of faith, see in the chapter on the Holy Spirit; for fire meaning the Divine good of love, see APOCALYPSE REVEALED 395, 468. These two are the means by which all regeneration is accomplished by the Lord.
The reason why the Lord Himself was baptised by John (Matt. 3:13-17; Mark 1:9; Luke 3:21, 22) was not only to introduce the practice of baptism for the future and to lead the way by His example, but also because He glorified His Human and made this Divine, just as He regenerates a person and makes him spiritual.