Jamieson, Fausset and Brown on 1 Corinthians 15:44

44. a natural body--literally, "an animal body," a body moulded in its organism of "flesh and blood" (1Co 15:50) to suit the animal soul which predominates in it. The Holy Spirit in the spirit of believers, indeed, is an earnest of a superior state (Ro 8:11), but meanwhile in the body the animal soul preponderates; hereafter the Spirit shall predominate, and the animal soul be duly subordinate.

spiritual body--a body wholly moulded by the Spirit, and its organism not conformed to the lower and animal (Lu 20:35, 36), but to the higher and spiritual, life (compare 1Co 2:14; 1Th 5:23).

There is, &c.--The oldest manuscripts read, "IF there is a natural (or animal-souled) body, there is also a spiritual body." It is no more wonderful a thing, that there should be a body fitted to the capacities and want of man's highest part, his spirit (which we see to be the case), than that there should be one fitted to the capacities and wants of his subordinate part, the animal soul [Alford].