Adam Clarke on 2 Corinthians 12:1

It is not expedient for me - There are several various readings on this verse which are too minute to be noticed here; they seem in effect to represent the verse thus: "If it be expedient to glory, (which does not become me), I will proceed to visions," etc. The plain meaning of the apostle, in this and the preceding chapter, in reference to glorying is, that though to boast in any attainments, or in what God did by him, was in all possible cases to be avoided, as being contrary to the humility and simplicity of the Gospel; yet the circumstances in which he was found, in reference to the Corinthian Church, and his detractors there, rendered it absolutely necessary; not for his personal vindication, but for the honor of the Gospel, the credit of which was certainly at stake.

I will come to visions - Οπτασιας· Symbolical representations of spiritual and celestial things, in which matters of the deepest importance are exhibited to the eye of the mind by a variety of emblems, the nature and properties of which serve to illustrate those spiritual things.

Revelations - Αποκαλυψεις· A manifestation of things not before known, and such as God alone can make known, because they are a part of his own inscrutable counsels.