Fr. Romanus Cessario, O.P., on the Development of Habitus

"The intrinsic relationship between the formation of habitus and the ability to exercise freely certain kinds of activity means that habitus can develop in the intellect, the will, and, to the extent that they follow right reason, the sense appetites. Finally, habitus development does not take place in anyone without the exercise of some agency. Theological ethics must hold that habitus develop either as a result of human agency or, according to the teaching of the faith, as a result of divine benevolence. 

"In the latter case, because they result directly from the power of the Holy Spirit, the habitus are called infused. Since the New Testament kerygma announces that divine grace effects a twofold change in creatures made after the image of God, infused habitus serve to elucidate the biblical doctrine of justification quite well.

"First, image-restoration consists in the rectification of disordered appetite. This constitutes, in effect, the breaking of old, vicious habitus. 

"Second, image-perfection entails the acquisition of the whole panoply of graced-endowments. These include the habitus of the moral virtues, of the theological virtues, and of the gifts of the Holy Spirit as well as the enjoyment of the fruits of the Spirit and the practice of the beatitudes."

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