Baptism in and of itself doesn't confer salvation. However, for a
believer it an expression of identification with Christ and a commitment to follow him. It is expected of all believers in obedience to the Lord and symbolizes the believers death and burial with Christ and his being raised with Him to live a new life.
See Mt 28:19, Acts 2:41; 8:12, 35-39; 10:44-48; 16:14-15, 30-33; 18:8; 19:4-5; Ro 6:3-4; Col 2:12