Yes, baptism IS a requirement.
Mark 16:16, He that believeth and is baptized shall be saved; but he that believeth not shall be damned.
John 3:5, Verily, verily, I say unto thee, except a man be born of the water and the Spirit he cannot enter into the kingdom of God.
Acts 8:36-39: And as they went on their way they came unto a certain water: and the eunuch said, See here is water, what doth hinder me to be baptized? And Philip said, If thou believest with all thine heart, thou mayest. And he answered and said, "I believe that Jesus Christ is the Son of God". And he commanded the chariot to stand still: and they went down both into the water, both Philip and the Eunuch; and he baptized him. And when they were come up out of the water, the Spirit of the Lord caught away Philip, that the eunuch saw him no more: and he went on his way rejoicing.
Acts 9:18: And immediately there fell from his [Saul/Paul's] eyes as it had been scales: and he received sight forthwith, and arose, and was baptized.
Acts 10:47: Can any man forbid water, that these should not be baptized, which have received the Holy Ghost as well as we? And he commanded them to be baptized in the name of the Lord. Then prayed they him to tarry certain days.
Romans 6:3-4: Know ye not, that so many of us as were baptized into Jesus Christ were baptized into his death. Therefore we are buried with him by baptism into death: that like as Christ was raised up from the dead by the Glory of the Father, even so we also should walk in newness of life.
Colossians 2:10-12: And ye are complete in him [Jesus], which is the head of all principality and power: In whom also ye are circumcised with the circumcision made without hands, in putting of the body of the sins of the flesh by the circumcision of Christ: Buried with Him in baptism wherein also ye are risen with him through the faith of the operation of God, who raised Him from the dead.
Every time when someone professed Jesus as Lord they were baptized in the Name of the Lord Jesus Christ for the remission of sin. Can we do less or ignore the express commands of the Lord?
Apostolic Believer In One God, Jesus