The two main propositions contained in this verse are the following the first, Flesh and blood is corruption; the second, The kingdom of God is incorruption.
I. Flesh and blood is corruption. To say that bodies corrupted by sin, or by the fall, cannot enter heaven would be simply an irrelevant truism, and would be held to be so by the parties with whom Paul is dealing. It is the admission, or the assertion, that flesh and blood, even in its best state, is corruption, and cannot therefore inherit incorruption; which alone meets their view fairly, and lays the foundation for the inference or conclusion that what is composed of flesh and blood must be changed into something better. The corruption, then, here spoken of is not an evil quality or effect superinduced on the bodily frame by sin; it is the essential property of flesh and blood, as originally made. (1) The body necessarily limits and renders fragmentary any knowledge of the Godhead. (2) It is the antagonist of the Divine life in us; we have to wrestle against it. (3) It has become mortal. On account of sin it is doomed to die. Remaining on the earth unchanged, flesh and blood is sure to die. The sentence on guilty man, "Dust thou art, and unto dust shalt thou return," takes full and universal effect. "His breath goeth forth; he returneth to his earth."
II. The kingdom of God is incorruption. It is a state or condition of things in which there is nothing perishable, no corruption. What it is positively is not here said. The kingdom of God, the heavenly world in a word, heaven is not here described. The elements which enter into its pure and holy joy are not specified. But it is identified with incorruption. (1) Death is out of the question, and hence there can be no room or occasion for such arrangements as are here necessary to stave off death. (2) In the kingdom of God there can be nothing to intercept or obscure the beatific heavenly blessedness of the pure in heart.
R. S. Candlish, Life in a Risen Saviour,p. 206.
Reference: 1 Corinthians 15:50-58. Preacher's Monthly,vol. i., p. 346.