These things I command you — i.e., the things of which He has spoken from John 15:1 onwards, and especially from John 15:12-16. After speaking them He comes back to the purpose from which this section started, “that ye love one another.”
We must beware of the not unfrequent mistake of interpreting “these things” of the words which follow, as if it were, “I command you this, viz., to love one another.” The thought is, “I am giving you these precepts that you may love one another.”