Between the two ideas of essentialisation and of substitution comes that of gradual _transformation_, which, again, cannot in history be separated from the other two. It has the obvious advantage of not regarding deification as an _opus operatum_, but as a process, as a hope rather than a fact. A favourite maxim with mystics who thought thus, was that "love changes the lover into the beloved." Louis of Granada often recurs to this thought. The best mystics rightly see in the doctrine of the Divinity of Christ the best safeguard against the extravagances to which the notion of deification easily leads. Particularly instructive here are the warnings which are repeated again and again in the _Theologia Germanica_. "The false light dreameth itself to be God, and taketh to itself what belongeth to God as God is in eternity without the creature. Now, God in eternity is without contradiction, suffering, and grief, and nothing can hurt or vex Him. But with God when He is made man it is otherwise." "Therefore the false light thinketh and declareth itself to be above all works, words, customs, laws, and order, and above that life which Christ led in the body which He possessed in His holy human nature. So likewise it professeth to remain unmoved by any of the creature's works; whether they be good or evil, against God or not, is all alike to it; and it keepeth itself apart from all things, like God in eternity; and all that belongeth to God and to no creature it taketh to itself, and vainly dreameth that this belongeth to it." "It doth not set up to be Christ, but the eternal God. And this is because Christ's life is distasteful and burdensome to nature, therefore it will have nothing to do with it; but to be God in eternity and not man, or to be Christ as He was after His resurrection, is all easy and pleasant and comfortable to nature, and so it holdeth it to be best."