1 Corinthians 15:44

It is sown a natural body. It dies as it lived: its life was vegetative and sensitive, and needed for its support food and drink, like the life of other animals. So, too, it was solid, inert, unable to give place to other bodies, and impenetrable. Such was the body of Adam, even in Paradise. The natural body is one that eats, drinks, sleeps, digests, toils, suffers fatigue, is heavy, and offers resistance to other bodies.

It is raised a spiritual body. 1. Not that the body is to be changed into a spirit or into an aërial body, as Origen and Eutychius, Patriarch of Constantinople in the time of S. Gregory, thought (he was convinced by S. Gregory and abandoned his error), but spiritual in the sense of being wholly subject and conformed to the spirit, so that it no longer stands in need of food or drink, it toils not, and feels no weariness, but is, so to speak, heavenly and deified, and, as Tertullian says, is, as it were, changed into the angelic nature. So S. Augustine (de Fide et Symb. c. 6) says: " It is called a spiritual body, not because it is changed into spirit, but because it is so subdued to the spirit that it is fitted for its heavenly dwelling-place, when all weakness and earthly frailty have been taken away, and transformed into celestial strength." Yet (c. 10) he seems to say that in the resurrection the body will not be of the flesh, but like that of angels. He retracts this, however, afterwards (Retract. lib. i. c. 17), and more at length (de Civ. Dei, lib . ult. c. 5 and 21).

2. Spiritual denotes subtilty, freedom from that heaviness and solidity that fills space, i.e., from that property of body by which it so fills space as to exclude all other bodies. The spiritual body will be subtle, as free from this property, and able, like spirit, to penetrate and fill all other bodies. Cf. Damascene (de Fide, lib. iv. c. 28) and Epiphanius (in Hæres. Orig.). For, as God can take from man his property, viz., the power of laughing, and can take from fire the heat which is the property of fire, so from body can He take away solidity, which is the property of natural bodily substance.