Adam Clarke on 2 Corinthians 5:13

Beside ourselves - Probably he was reputed by some to be deranged. Festus thought so: Paul, thou art beside thyself; too much learning hath made thee mad. And his enemies at Corinth might insinuate not only that he was deranged, but attribute his derangement to a less worthy cause than intense study and deep learning.

It is to God - If we do appear, in speaking of the glories of the eternal world, to be transported beyond ourselves, it is through the good hand of our God upon us, and we do it to promote his honor.

Whether we be sober - Speak of Divine things in a more cool and dispassionate manner, it is that we may the better instruct and encourage you.