For this,
You shall not commit adultery, You shall not kill, You shall not steal, You shall not bear false witness, You shall not covet;
and if there be any other commandment, it is summed up in this saying, namely,
You shall love your neighbor as yourself.
Read Chapter 13
Ambrosiaster
AD 400
Moses wrote all this in order to reform the natural law. … Although there may be other laws which Paul has not mentioned, love is the fulfillment of them all. For if the human race had loved from the beginning, there would never have been any wickedness on earth. For the result of unrighteousness is discord. Commentary on Paul’s Epistles.
No one loves his neighbor unless he loves God, and by loving him as himself, to the limit of his ability, he pours out his love on him so that he too may love God. But if he does not love God, he loves neither himself nor his neighbor.
The beginning and the end of virtue is love…. But Paul is not looking merely for love; he wants it to be an intense love. For he does not say merely: “Love your neighbor,” but adds: “as yourself.” Christ himself said that the law and the prophets hang upon this.
All the precepts which afterwards sprouted forth when given through Moses; that is, Thou shalt love the Lord thy God from thy whole heart and out of thy whole soul; Thou shalt love thy neighbour as thyself;.
Very properly, then, did he sum up the entire teaching of the Creator in this precept of His: "Thou shalt love thy neighbour as thyself.".
Are we to paint ourselves out that our neighbours may perish? Where, then, is (the command), "Thou shall love thy neighbour as thyself? "