We have two principles of action - duty and love. The first follows the law of being, the second the lure of love. To do one's duty is really nothing else than to fulfil the purpose of existence. It is the natural development of being itself. The duty of the soul or the duty of the body signifies just that - the soul using to the fullest its every power, the body putting to the highest exercise all the wonderful capacities given it and using them for the purposes for which they were intended. That is the law of duty, the law which bids us put into practice the latent faculties of our nature. But love is the attraction which beauty sets to the will under the impulse of discerning reason; that is to say, when we love, it is because reason (outpacing or roughly guided by sentiment) has discovered something that calls from our heart an echo, something to which we eagerly go forward. Even to love oneself is nothing else than to discover in oneself, by a reflex act, that there are certain excellences in us which appeal strongly to us - make us, as it were, go out to ourselves all the more yearningly because it is ourselves. Hence we can sum up the life of man in his double activity. He does his duty, he loves what is lovely. The ideas described in the words "ought," "must," etc., the feeling of a moral obligation, are responsible for one half of human actions; the other half are governed by the appeal made to us by things, people, actions, that draw us to them. Doing my duty, loving the loveable, is the sum total of my life.
Now we can say, with obvious modifications, that these two laws can be found also in God Himself. The forces whereby God the Father, in our human language, begot the Son, and whereby from the Father and the Son proceeded the Holy Ghost, are termed not free but natural. That is the precise phrase of the theologian, by which he endeavours to say, in language that is of scientific construction, that the Father in knowing Himself in the Son and loving Himself in the Holy Spirit could not have done otherwise, could not have chosen otherwise. He was not free to have acted differently. Not, of course, that He was compelled to this by some higher power, for there can be no higher power than God: but it is out of the very essence of His own being that this act of life comes. Again, too, it should be noted that when we say of God that He loves anything that He has made, we cannot suppose that His love is caught by something outside of Himself. He cannot be affected by anything that is outside of Him, else would He not be sole, independent God. What He sees in us worthy of love, is not us, but His own reflection: He is enamoured of the loveliness of Himself. That is, we must not look upon Him as at all influenced by any higher power, for He is Himself the highest power that is. We repeat, then, that it is in a more excellent way that God is affected by these two laws. He fulfils the law of duty and the law of love. He is affected by His Being, which is self-existing, and by His Beauty, which is uncreated, for His Being and His Beauty and Himself are one.
Yet there is also a third law, which is goodness. It consults no interest, awaits no command, and solicits no attraction of beauty. In a sense it includes in itself the law of being in so far as it is a spontaneous movement of its nature, and the law of beauty in so far as goodness is beauty's highest perfection. Yet in a sense, too, it seems nobler than both; for it was divine beauty and divine being that were led by Divine Goodness to create the world. There was certainly no obligation on God's part to call the world into existence. We are compelled by our belief in God to say that He had no need for us. He could have been perfectly happy without us: hence we cannot say that His nature forced Him to have us. Neither, as we have explained above, could we pretend that God could see in us any beauty that attracted Him and was not already part of Himself. We did not even influence Him to create us. Consequently we have to suppose some sort of divine generosity which, apart from the movement of His nature, led Him to make the world. It was as though "He heard the cry of worlds that were not, the cry of unmeasured misery calling to unbounded goodness." My attitude, therefore, to God must be one of intense thankfulness that I have had the gift of life, that with His own perfect generosity, without any advantage to Himself (though indeed finding pleasure in it), He began the world. And all the subsequent kindnesses lavished on me are again not demanded from Him by Himself, but are the spontaneous gift of His goodness.
- text taken from Meditations for Layfolk by Father Bede Jarrett, O.P.