Albert Barnes Commentary Acts 8:37

"[And Philip said, If thou believest with all thy heart, thou mayest. And he answered and said, I believe that Jesus Christ is the Son of God.]" — Acts 8:37 (ASV)

And Philip said, etc. This was then stated to be the proper qualification for making a profession of religion. The terms are:

1. Faith, that is, a reception of Jesus as a Savior, yielding the mind to the proper influences of the truths of redemption (see Barnes on Mark 16:16).
2. There is required not merely the assent of the understanding, but a surrender of the heart, the will, the affections, to the truth of the gospel. As these were the proper qualifications then, so they are now. Nothing less is required, and nothing but this can constitute a proper qualification for the Lord's Supper.

I believe, etc. This profession is more than a professed belief that Jesus was the Messiah. The name Christ implies that. "I believe that Jesus the Messiah" is, etc. In addition to this, he professed his belief that he was the Son of God—showing either that he had before supposed that the Messiah would be the Son of God, or that Philip had instructed him on that point.

It was natural for Philip, in discussing the humiliation and poverty of Jesus, to add also that he sustained a higher rank of being than a man and was the Son of God.

What precise ideas the eunuch attached to this expression cannot now be determined. This verse is missing from a very large number of manuscripts (Mill) and has been rejected by many of the ablest critics.

It is also omitted in the Syriac and Ethiopic versions. It is not easy to conceive why it has been omitted in almost all the Greek manuscripts, unless it is spurious.

If it was not in the original copy of the Acts, it was probably inserted by some early transcriber and was deemed so important to the connection—to show that the eunuch was not admitted hastily to baptism—that it was afterward retained. It contains, however, an important truth, elsewhere abundantly taught in the Scriptures: that faith is necessary to a proper profession of religion.