Baptism is the new circumsision.
In him you were also circumcised with a circumcision not administered by hand, by stripping off the carnal body, with the circumcision of Christ. You were buried with him in baptism, in which you were also raised with him through faith in the power of God, who raised him from the dead.
Col 2:10-11
This prefigured baptism, which saves you now. It is not a removal of dirt from the body but an appeal to God 7 for a clear conscience, through the resurrection of Jesus Christ.
1 Peter 3:21
The phrase "not as a removal of dirt from the body" is in referecne to the Jewish ceremony of circumcision. Baptism is now the “circumcision” of the new Covenant (Col. 2:11-12), but it, unlike the old circumcision, actually saves us, as Noah and his family were saved by water.
Church Fathers: "We are circumcised not with a fleshly circumcision but with the circumcision of Christ, that is, we are born again into a new man; for, being buried with Him in His baptism, we must die to the old man, because the regeneration of baptism has the force of resurrection." Hilary of Poitiers, Trinity, 9:9 (A.D. 359).
"But in respect of the case of the infants, which you say ought not to be baptized within the second or third day after their birth, and that the law of ancient circumcision should be regarded, so that you think one who is just born should not be baptized and sanctified within the eighth day...And therefore, dearest brother, this was our opinion in council, that by us no one ought to be hindered from baptism...we think is to be even more observed in respect of infants and newly-born personsÂ…" Cyprian, To Fidus, Epistle 58(64):2, 6 (A.D. 251).