Love is the hardest lesson in Christianity; but, for that reason, it should be most our care to learn it.
From Mark 12:29-31: “Jesus answered, ‘The first is, Hear, O Israel: the Lord our God, the Lord is one; you shall love the Lord your God with all your heart, and with all your soul, and with all your mind, and with all your strength. The second is this, You shall love your neighbor as yourself. There is no other commandment greater than these.'”