John 12:49

For I have not spoken of myself - I have not spoken for my secular interest: I have not aimed at making any gain of you: I have not set up myself as your teachers in general do, to be supported by my disciples, and to be credited on my own testimony. I have taught you, not the things of men, but the deep, everlasting truths of God. As his envoy, I came to you; and his truth only I proclaim.

Gave me a commandment - Or, commission. So I understand the original word, εντολη . Christ, as the Messiah, received his commission from God; what he should command - every thing that related to the formation and establishment of the Christian institution: and what he should speak - all his private conversations with his disciples or others, he, as man, commanded and spoke through the constant inspiration of the Holy Spirit.