'Command of the Lord' in the Bible

And concerning the virgins, a command of the Lord I have not; and I give judgment as having obtained kindness from the Lord to be faithful:

If anyone thinks and claims that he is a prophet [a true spokesman for God] or spiritually astute [filled with and energized by the Holy Spirit], let him recognize that the things which I write to you are the Lord’s commandment.

If anyone does not recognize this [that it is a command of the Lord], he is not recognized [by God].