Baptism: Is it necessary for Salvation?

Baptism was and always has been performed using water.  Throughout scripture baptism is placed with washing away our sins.  Some Protestant groups claim that baptism is not necessary,

For example Billy Graham,

"Make it happen now. …If you are willing to repent for your sins and to receive Jesus Christ as your Lord and Savior, you can do it now. At this moment you can either bow your head or get on your knees and say this little prayer which I have used with thousands of persons on every continent: O God, I acknowledge that I have sinned against You. I am sorry for my sins. I am willing to turn from my sins. I openly receive and acknowledge Jesus Christ as my Savior. I confess Him as Lord. From this moment on I want to live for Him and serve Him. In Jesus’ name. Amen. …If you are willing to make this decision and have received Jesus Christ as your own Lord and Savior, then you have become a child of God in whom Jesus Christ dwells. …You are born again (pp. 168-169, How to Be Born Again).  "

If you were to learn from Early Christians what Baptism is and how its done, who would you follow Billy Graham or the Early Church?

The Didache

"After the foregoing instructions, baptize in the name of the Father, and of the Son, and of the Holy Spirit, in living [running] water. If you have no living water, then baptize in other water, and if you are not able in cold, then in warm. If you have neither, pour water three times on the head, in the name of the Father, and of the Son, and of the Holy Spirit. Before baptism, let the one baptizing and the one to be baptized fast, as also any others who are able. Command the one who is to be baptized to fast beforehand for one or two days" (Didache 7:1 [A.D. 70]). "

Hippolytus

"When the one being baptized goes down into the water, the one baptizing him shall put his hand on him and speak thus: ‘Do you believe in God, the Father Almighty?’ And he that is being baptized shall say: ‘I believe.’ Then, having his hand imposed upon the head of the one to be baptized, he shall baptize him once. Then he shall say: ‘Do you believe in Christ Jesus . . . ?’ And when he says: ‘I believe,’ he is baptized again. Again shall he say: ‘Do you believe in the Holy Spirit and the holy Church and the resurrection of the flesh?’ The one being baptized then says: ‘I believe.’ And so he is baptized a third time" (The Apostolic Tradition 21 [A.D. 215]). "

Justin Martyr

"As many as are persuaded and believe that what we [Christians] teach and say is true, and undertake to be able to live accordingly, and instructed to pray and to entreat God with fasting, for the remission of their sins that are past, we pray and fast with them. Then they are brought by us where there is water and are regenerated in the same manner in which we were ourselves regenerated. For, in the name of God, the Father . . . and of our Savior Jesus Christ, and of the Holy Spirit [Matt. 28:19], they then receive the washing with water. For Christ also said, ‘Unless you are born again, you shall not enter into the kingdom of heaven’ [John 3:3]" (First Apology 61 [A.D. 151])."

Basil the Great

"This then is what it means to be ‘born again of water and Spirit’: Just as our dying is effected in the water [Rom. 6:3; Col. 2:12–13], our living is wrought through the Spirit. In three immersions and an equal number of invocations the great mystery of baptism is completed in such a way that the type of death may be shown figuratively, and that by the handing on of divine knowledge the souls of the baptized may be illuminated. If, therefore, there is any grace in the water, it is not from the nature of water, but from the Spirit’s presence there" (The Holy Spirit 15:35 [A.D. 375])."

The Apostolic Constitutions

"Be ye likewise contented with one baptism alone, that which is into the death of the Lord [Rom. 6:3; Col. 2:12–13]. . . . [H]e that out of contempt will not be baptized shall be condemned as an unbeliever and shall be reproached as ungrateful and foolish. For the Lord says, ‘Except a man be baptized of water and of the Spirit, he shall by no means enter into the kingdom of heaven.’ And again, ‘He that believes and is baptized shall be saved, but he that believes not shall be damned’" [Mark 16:16] (Apostolic Constitutions 6:3:15 [A.D. 400]).

Augustine

"It is this one Spirit who makes it possible for an infant to be regenerated . . . when that infant is brought to baptism; and it is through this one Spirit that the infant so presented is reborn. For it is not written, ‘Unless a man be born again by the will of his parents’ or ‘by the faith of those presenting him or ministering to him,’ but, ‘Unless a man be born again of water and the Holy Spirit.’ The water, therefore, manifesting exteriorly the sacrament of grace, and the Spirit effecting interiorly the benefit of grace, both regenerate in one Christ that man who was generated in Adam" (Letters 98:2 [A.D. 412]).

"Those who, though they have not received the washing of regeneration, die for the confession of Christ—it avails them just as much for the forgiveness of their sins as if they had been washed in the sacred font of baptism. For he that said, ‘If anyone is not reborn of water and the Spirit, he will not enter the kingdom of heaven,’ made an exception for them in that other statement in which he says no less generally, ‘Whoever confesses me before men, I too will confess him before my Father, who is in heaven’" [Matt. 10:32] (The City of God 13:7 [A.D. 419]).