From Treatise on the Love of God Book I, Chapter XV:
This pleasure, this confidence which man's heart naturally has in God, can spring from no other root than the affinity there is between this divine goodness and man's soul, a great but secret affinity, an affinity which each one knows but few understand, an affinity which cannot be denied nor yet be easily sounded. We are created to the image and likeness of God:—what does this mean but that we have an extreme affinity with his divine majesty?
Our soul is spiritual, indivisible, immortal; understands and wills freely, is capable of judging, reasoning, knowing, and of having virtues, in which it resembles God. It resides whole in the whole body, and whole in every part thereof, as the divinity is all in all the world, and all in every part thereof. Man knows and loves himself by produced and expressed acts of his understanding and will, which proceeding from the understanding and the will, and distinct from one another, yet are and remain inseparably united in the soul, and in the faculties from whence they proceed. So the Son proceeds from the Father as his knowledge expressed, and the Holy Ghost as love breathed forth and produced from the Father and the Son, both the Persons being distinct from one another and from the Father, and yet inseparable and united, or rather one same, sole, simple, and entirely one indivisible divinity.
But besides this affinity of likenesses, there is an incomparable correspondence between God and man, for their reciprocal perfection: not that God can receive any perfection from man, but because as man cannot be perfected but by the divine goodness, so the divine goodness can scarcely so well exercise its perfection outside itself, as upon our humanity: the one has great want and capacity to receive good, the other great abundance and inclination to bestow it.