Paul makes a connection between baptism and circumcision, noting that baptism is the new covenant sacrament that replaces circumcision (Col. 2:11–12). As such, spiritual realities such as regeneration that are signed and sealed by new covenant baptism were signed and sealed by old covenant circumcision. Thus, knowing when the grace of regeneration exhibited in circumcision took effect in the circumcised old covenant saints gives us a better understanding of when the grace of regeneration exhibited in baptism takes effect for those who are baptized under the new covenant.
So, when were circumcised old covenant individuals actually regenerated in relation to the time of their circumcision? It varied from individual to individual. Some old covenant saints were clearly regenerated, given new hearts able to believe God’s promises, before they were circumcised. Abraham, for instance, believed God before he was circumcised (Gen. 15:6; 17:23–24; Rom. 4:11–12). Other old covenant believers received new hearts after circumcision. Isaac, for example, was circumcised at eight days old, but his faith did not come until he was older (Gen. 21:4; 26:1–4). Moreover, that Jeremiah calls on those circumcised in the flesh to be circumcised in the heart assumes it was possible to have received the old covenant sacrament of circumcision and yet not be regenerated until later (Jer. 4:3–4).
God stands outside and over time as its Lord, declaring the end from the beginning (Isa. 46:8–11). He sovereignly chooses whom and when to regenerate. There was no necessary time connection between old covenant circumcision and regeneration. Some were circumcised before being regenerated, some after. Furthermore, Scripture gives us no prescription telling us that regeneration must happen before, during, or after new covenant baptism. Regeneration could happen before, during, or after circumcision. Apart from a clear statement that God is now mandating a certain order of baptism and regeneration, we have little reason to believe that in the new covenant, the sign of regeneration has a necessary time relation to the actual event of regeneration.
Therefore, the New Testament accounts of those who were baptized after believing in Jesus, such as today’s passage, should not be given prescriptive weight. They only describe what is true for some people in the new covenant era. They do not mandate that we wait to baptize individuals until after they profess faith.