John the Apostle
John 3:11ESV·traditional attribution

Truly, truly, I say to you, we speak of what we know, and bear witness to what we have seen, but you do not receive our testimony.

John Calvin Reformed @genevareformer

11. We speak what we know. Some refer this to Christ and John the Baptist; others say that the plural number is used instead of the singular. For my own part, I have no doubt that Christ mentions himself in connection with all the prophets of God, and speaks generally in the person of all.

Matthew Henry Presbyterian @wholebiblehenry

We found, in the close of the foregoing chapter, that few were brought to Christ at Jerusalem; yet here was one, a considerable one. It is worth while to go a great way for the salvation though but of one soul. Observe, I. Who this Nicodemus was. Not many mighty and noble are called; yet some are, and here was one.

Commenting on John 3:1-21

John Gill Reformed Baptist @doctorgill

If I have told you earthly things,.... Not that the doctrines he delivered were earthly ones; for he was not of the earth, but from heaven, and above all, and so spake not of the earth, but of heaven, Joh 3:31; and this doctrine of regeneration was an heavenly doctrine; and the thing itself required supernatural power, and grace from above: but either they were...