1. Baptism is the immersion in water of a penitent believer.
Acts 8:36-39 says:
As they traveled along the road, they came to some water and the eunuch said, “Look, here is water. Why shouldn’t I be baptized?” And he gave orders to stop the chariot. Then both Philip and the eunuch went down into the water and Philip baptized him. When they came up out of the water, the Spirit of the Lord suddenly took Philip away, and the eunuch did not see him again, but went on his way rejoicing.”
Baptism, without further qualification, refers to the act of being immersed in water. If the word is being used in a figurative sense, then something more is added (i.e., baptized with the Spirit, baptized with fire, etc.), or the context will indicate some non-literal baptism (see Mark 10:38ff). Baptism involves much water (John 3:23), going down into the water, being buried and raised (Romans 6:4ff). These all clearly point to the act of immersion rather than pouring or sprinkling.
2. Baptism is part of what people do when they come to God.
It’s a genuine tragedy that in our time baptism is viewed as such a divisive, controversial issue. I’ll leave you to draw your own conclusions as to how and why that has happened. The only point I wish to make is that the New Testament’s teaching on baptism is remarkably straightforward. A cursory reading of the book of Acts will yield the conclusion that baptism is part of the process of coming to God. The eunuch goes on his way rejoicing—after his baptism (8:39). The jailer at Philippi is filled with joy—after he is baptized (16:34). Those who were baptized at Pentecost were said to have received Peter’s message concerning Jesus (2:41). Even when there were special circumstances involved (Acts 10:44ff; Acts 19:1-6), baptism was still involved in coming to God. The N.T. writers never think to argue this (as we would today), they assume it. It’s not hard to see a pattern here. Baptism is part of what is involved in people coming to God.
3. Baptism is part of the message about Jesus.
The eunuch in Acts 8:26ff is returning to his homeland after worshiping in Jerusalem. He is reading from an Isaiah scroll. The evangelist Philip is invited by the eunuch to expound upon the Isaiah text (chapter 53). Luke writes these words:
Then Philip began with that very passage of Scripture and told him the good news about Jesus (v. 35).
Luke then records this:
As they traveled along the road, they came to some water and the eunuch said, “Look, here is water. Why shouldn’t I be baptized?” (v. 36).
It seems clear that Luke means for us to understand that as Philip shared the good news of Jesus with the eunuch, baptism was part of his message. Moreover, the eunuch understood that and when the first opportunity came for him to be immersed he wanted to know why he couldn’t go ahead and do that. Baptism is part of the message of Jesus!