The Lord asks only two things of us: love for his Majesty and love for our neighbor. It is for these two virtues that we must strive, and if we attain them perfectly we are doing his will and so shall be united with him … The surest sign that we are keeping these commandments is, I think, that we should really be loving our neighbor: for we cannot be sure if we are loving God, although we may have good reasons for believing that we are, but we can know quite well if we are loving our neighbor. And be certain that, the farther advanced you find you are in this, the greater the love you will have for God.
–Saint Teresa of Avila (1515-1582)