That's one indication that water baptism is not what was being referred to. They were clearly speaking of the baptism of the Spirit. If this were not the case the Bible would be full of inconsistencies and contradictions and would therefore, invalidate itself. Clearly, it's becoming increasingly apparent that salvation is won through belief in Christ only and that baptism with water is a visible expression of what takes place when we receive the Holy Spirit. Here we find that first we believe and then we are sealed by the Holy Spirit through baptism of the Spirit.
Nothing is said of baptism with water being necessary for salvation.
But the baptism of the Holy Spirit is quite obvious. And surely I am with you always, to the very end of the age. The purpose of the local church, as we find here, is to make disciples of all kinds of people. Those who are evangelized and converted should then be baptized, attesting to their identification with Christ and the local body of believers. Again, water baptism is not mentioned to be a part of salvation.