Water baptism is an act of identification by faith; we receive a new status or identity in God. We are Christians because we belong to Christ. Baptism effectively joins us both to Christ and to His people. But this change also means the surrender of our old identity. Before putting on Christ in water baptism, our identity was defined in terms of our reference groups in this world: nationality, economic and social status, sex roles, and the like. But these become meaningless in defining who we are once we are thoroughly identified with Christ.
We become Abraham’s seed and inherit his promises.
The Jews prided themselves in being descendants of Abraham, but they had lost the central ingredient that had made Abraham the Friend of God: faith. Instead, they were relying upon external identity. God was now making the difference between those who were His and those who were not. The true Jew or child of Abraham was now one on the inside, in the heart.
For he is not a Jew, which is one outwardly; neither is that circumcision, which is outward in the flesh: But he is a Jew, which is one inwardly; and circumcision is that of the heart, in the spirit, and not in the letter; whose praise is not of men, but of God (Romans 2:28, 29).
We put on Christ himself.
We are not only baptized into the name of Christ and into His rule or Lordship, but into Him. For this reason, we can expect to live a completely new kind of life. We are no longer on our own. We have been caught up into the purposes of God. The center of our affections is no longer on ourselves.
Set your affection on things above, not on things on the earth. For ye are dead, and your life is hid with Christ in God (Colossians 3:2, 3).
We are placed in the Body of Christ.
Living for God is not as individualistic as we Americans would like to think. God desires a corporate expression of himself in the Earth. He picks us out of the world and makes us not only members of himself, but of each other. This spiritual bond takes place through water baptism.
For by one Spirit are we all baptized into one body, whether we be Jews or Gentiles, whether we be bond or free; and have been all made to drink into one Spirit. For the body is not one member, but many (1 Corinthians 12:13, 14).