Term it what you will, but it is a commandment that the believer must be obedient to. Symbolic, yes, as aforementioned.
At the moment of repentance/acceptance, God’s Holy Spirit (HS) enters believers’ spiritual hearts (RV 3:20), uniting them with God as heavenly Father (RM 8:9) and identifying them with Christ’s worldwide/catholic body or church (CL 1:18). Paul referred to the comparable moment for Abraham as spiritual circumcision. This manifold event is also called spiritual birth or baptism (1CR 12:13).
We can infer that this dynamic occurs also for pre-NT believers like Abraham, because there is no salvation outside of Christ’s
ekklesia or church (ACTS 4:12). Partial knowledge of God’s Word will limit ability to cooperate with Him, so there is a need for evangelism or learning the full Gospel (MT 28:18-20, cf. ACTS 18:24-26) as well as for lifelong discipleship or spiritual training (2TM 3:16-17). From the advent of Christ until the Second Coming is the third or New Covenant dispensation and relationship with God (RM 3:21-26, GL 3:24-25, HB 7:18-10:1).
Confusion may arise from the fact that in Ephesians 4:5 Paul says there is only one baptism, but elsewhere the NT seems to refer to two types of baptism: one by water and another by the HS. In His “Great Commission” Jesus tied saving faith closely to the work of water baptism when He said “Make disciples of all nations, baptizing them” (MT 28:19). Yet, in 1 Corinthians 12:13 Paul wrote that “We were all baptized by one Spirit into one body.” This suggests that spirit baptism occurs at the moment of conversion, when the HS unites the new saint (saved sinner/soul) with Christ, because “if anyone does not have the Spirit of Christ, he does not belong to Christ.” (RM 8:9) The indwelling of the HS may also be called the initial filling by the HS, because at the point of confession and conversion a person is cooperating fully with God. (See RM 6:3-7, GL 2:20) The evidence that a person has been baptized by God’s Spirit or included in Christ’s spiritual body is love in its myriad of forms (GL 5:22-23, JN 13:35).
Any confusion is resolved by understanding that
the two types of baptism are united if baptism with water is viewed as a symbolic way of portraying baptism by the HS. The details for this work are vague, but the mode of immersion best portrays a Believer’s spiritual union with Christ in His death, burial and resurrection to eternal life (CL 2:12, RM 6:4). As a practical matter, a new Believer normally would be baptized by the local congregation of the catholic (worldwide) church in which he/she will want to participate as an acknowledged member. Water baptism symbolizes spiritual baptism.
Instead of commanding water baptism for salvation, Paul said in one place (RM 10:9-10) that a convert should confess “with your mouth” in order to be saved, even though elsewhere (EPH 2:8-9) he taught that one is saved by faith. Both
outward confession and water baptism may be seen as works manifesting love for God that every new Believer will want to (but we cannot say “must”) perform as soon as possible following his/her decision to have saving faith (cf. MT 3:13-15, ACTS 2:38).
Although Paul did not command water baptism, he administered it (in ACTS 16:33, 18:8, 19:5 & 1CR 1:114-16) even though he said Christ did not send him to baptize but to preach the gospel (1CR 1:17). IOW, Paul’s focus was on preaching (spirit baptism) and he probably left the water baptizing to his assistants.