If love is a passion, and God has no passion, then why does Saint John say that God is love?
It is this very delicate question that Saint Thomas Aquinas raises, and to which he tries to give an answer.
Saint Thomas proceeds in three steps:
1. All appetitive movements (wanting, desiring, etc.) necessarily have loved as their root.
2. Now there is in God the will.
3. So there is love in God.
You can read the reflection of Saint Thomas Aquinas as follows:
Article 1 – Is there love in God?
1. It seems that it is not. For there is no passion in God. Love is a passion. So there is no love in God.
2. Love, anger, sadness, etc. are distinguished as opposites in the same kind. Now sadness and anger are attributed to God only by metaphor. So also love.
3. We read in Denys: “Love is a unifying force and a principle of cohesion. ‘But this cannot find a place in God, since he is simple. Such a force cannot be used in an absolutely simple being.
On the contrary, we read in S. John (1 Jn 4:16): “God is love. ”
Love is necessarily found in God. Indeed, the first movement of the will or of any appetitive faculty is love. For the act of the will, or the act of any appetite, is directed as to its own object towards good and towards evil. But the good is principally and inherently the object of the will as of every appetite; the evil secondarily by virtue of something else, that is, of the good to which it is opposed. It is therefore necessary that the acts of the will and of every appetite which look to the good have a natural priority over those which look to the evil: thus joy over sadness, and love over hatred; for what is such by itself is always prior to what is such only by something else.
Moreover, that which is more general is first by nature; this is why the intelligence first relates to the truth universally, and only then to particular truths. Now, there are acts of will or appetite which concern the good considered under some particular condition: thus joy, delight, is relative to the good present and possessed; desire and hope to the good not yet obtained. On the contrary, love relates to the good in general, whether it is possessed or not. It is therefore love which is by nature the primary act of the will or of the appetite.
It is for this reason that all appetitive movements presuppose love as their first root. We desire nothing else, in fact, but what is good and what we love; in nothing else do we find our joy. As for hatred, it is only directed at that which stands in the way of the thing loved. It is equally obvious that sadness and other similar movements refer to love as their first principle. From this we must conclude that in every being where there is some appetitive faculty, there must be loved; for by suppressing what is first, we suppress all that comes after. Now, we have shown that there is a will in God: it is necessary to affirm that there is love in him.
1. The cognitive power moves only through the intermediary of the appetitive power. And just as in us the reason which conceives the universal moves only by means of the particular reason, as it is said in the treatise on the soul: so the intellectual appetite called will sets us in motion by means of the sensory appetite. Thus what immediately makes the body move, to us, is the sensory appetite. From this it follows that an act of the sensory appetite is always accompanied by a bodily modification, mainly affecting the heart, which is the first principle of movement in the living. This is why the acts of the sensory appetite, as they are linked to a bodily alteration, are “passions”, and not acts of will. Love, therefore, and joy or delight, when they are acts of the sensory appetite, are passions; but not if they are acts of the intellectual appetite. But this is how we attribute them to God. This makes the philosopher say: “God enjoys a single and simple action. ‘In the same way, and for the same reason, he loves without this being a passion.
2. In the passions of the sensory appetite, we must distinguish between what is in some way material, namely bodily alteration, and what is formal, which comes from the appetite. Thus, in anger, as the treatise on the soul notes, what is material is the flow of blood to the heart, or anything of that kind; what is formal is the appetite for vengeance. But moreover, on the side of what is formal, some of these passions imply a certain imperfection; and for example, in desire is included the idea of a good not possessed, in sadness, that of an evil suffered. And it is the same with anger, which implies sadness. Other passions, like love and joy, do not imply any imperfection. Therefore, since there is nothing in these appetitive movements that is suitable for God as regards what is material in them, as we have just said, we can only attribute to God by metaphor what implies the same imperfection on the side of what is formal, in order to express the similarity of effects, as we have explained. But what does not involve any imperfection can be attributed to God in the proper sense, like love and joy, but excluding passion, as we have just said.
3. Love always tends towards two terms: the good thing it wants for someone, and the one for whom it wants it. To love someone is indeed to want for him what is good. This is why to love oneself is to want for oneself what is good, so that one seeks to unite it as much as one can. This is what is meant when we call love a unifying force, even in God, but without there being any composition of elements, because the good that God wants for himself is none other than himself, who is good by the essence, as we have shown previously. But to love another than oneself is to want what is good for him. Thus, it is to use it with him as with oneself, relating to him the good thing one loves, as to oneself. It is in this sense that love is called a principle of cohesion: because he who loves to integrate the other into himself, behaving with him as with himself. Divine love, too, is a force of cohesion, not because it introduces into God any kind of composition, but because God wants for others what is good.