"Jesus ... combines all duties (1) in one universal rule (which includes within itself both the inner and the outer moral relations of men), namely: Perform your duty for no motive other than unconditioned esteem for duty itself, i.e., love God (the Legislator of all duties) above all else; and (2) in a particular rule, that, namely, which concerns man’s external relation to other men as universal duty: Love every one as yourself, i.e., further his welfare from good-will that is immediate and not derived from motives of self-advantage. These commands are not mere laws of virtue but precepts of holiness which we ought to pursue, and the very pursuit of them is called virtue."
January 1, 1970
https://en.wikiquote.org/wiki/Duty