In What Does Human Love Center?

"No man can serve two masters: for either he will hate the one, and love the other; or else he will hold to the one, and despise the other. Ye cannot serve God and mammon." —  Matthew 6:2.

Of the various objects, to which love is directed, it will always be found, that those objects will not all be loved alike; but some will be loved more, and some less. Of two objects or of many objects which essentially differ in their attractions, in other words, in their power of exciting love, it can never be said that the soul loves them both, or that it loves them all in an equal degree. The love of the object will be in proportion to the attracting power of the object, considered in relation to the soul.

Among these various objects there will be some one, on which the love of the soul will rest and satisfy itself in the highest degree; in a degree which may be expressed by the term supremely. The soul, in the exercise of its affections, must necessarily have a centre of love somewhere: viz., in the object which is most beloved. And that object will be the most beloved, and will constitute the centre of love, which possesses for the soul the highest attractions. The love of other things, which have less attractions for the soul, cannot fail to be subordinate. It is true, that the soul may take a degree of satisfaction in those objects, which are inferior or subordinate in its love. But it is in the supreme object of its affections, and in that central and supreme object alone, that it will rest and delight itself with supreme satisfaction. It is there, emphatically, that the heart is. There is the centre, and it is infinitely important that every man should know what that centre is in his own case. 

The centre of man’s love, (we do not say his love, but the centre of his love,) must be either in himself, or in other creatures, or in God. He may love all in different degrees; and he may love all in that manner at the same time; but he cannot have a centre or supremacy of love in all at the same time. He either loves God supremely, or he loves other beings, which are inferior to God, supremely; or he loves himself supremely. There does not seem to be any other supposition to be made in the case.

— The Life of Faith, Part 2, Chapter 4.