Church Fathers on John 15:17

Our Lord had said, I have ordained that you should walk and bring forth fruit. Love is this fruit. Wherefore, He proceeds: These things I command you, that you love one another. Hence the Apostle said, The fruit of the Spirit is love(Gal 5:22), and enumerates all other graces as springing from this source. Well then does our Lord commend love, as if it were the only thing commanded: seeing that without it nothing can profit, with it nothing be wanting, whereby a man is made…

I have said that I lay down My life for you, and that I first chose you. I have said this not by way of reproach, but to induce you to love one another. Then as they were about to suffer persecution and reproach, He bids them not to grieve, but rejoice on that account: If the world hates you, you know that it hated Me before it hated you: as if to say, I know it is a hard trial, but you will endure it for My sake.

For the dispraise of the perverse, is our praise. There is nothing wrong in not pleasing those who do not please God. For no one can by one and the same act please God, and the enemies of God. He proves himself no friend to God, who pleases His enemy; and he whose soul is in subjection to the Truth, will have to contend with the enemies of that Truth.