Romans 1:21 : Because that, knowing God, they glorified him not as God, neither gave thanks; but became vain in their reasonings, and their senseless heart was darkened. These heathen nations had known God their knowledge of him had been sufficient to rob them of any excuse for their gross sins. But though they knew him, they did not glorify him as God. Their knowing him had been of no benefit to them; they had sinned against the light they had. To glorify God as God is to recognize him as the Creator, Preserver, and rightful Ruler of all things, and to seek earnestly to comply with his will--to do the work he intended us to do. In his prayer on the night of his betrayal, Jesus said: "I glorified thee on the earth, having accomplished the work which thou host given me to do" (John 17:4). Only in this way may we glorify him. If a machine fails to do the work which it was made to do, it certainly reflects no glory on the one who made it but if it does perfectly the work it was designed to do, it glorifies its maker. If any of our inventions, plans, or purposes succeed, we thereby bring worldly glory upon ourselves. In the very nature of the case it cannot be otherwise. It is therefore impossible to glorify God by our own plans and purposes, no matter how successful they may seem to be. Only by doing the things he designed we should do can we glorify him. Herein the nations had miserably failed. And having put God out of their philosophy of things, there was no longer any gratitude in their hearts to the Giver of all good things. When people deny God, they are, of course, not thankful. They became vain in their reasonings--that is, their speculations were foolish and without value. How else could they be? There can be no solid process of reasoning without a starting point, and no process of reasoning that eliminates God has any starting point. It must begin with a guess, an assumption, and proceed in the dark. If God did not create the universe, then any theory as to its origin is a blind guess. If God did not create us, then any theory as to the origin of life and as to how we became human beings is found-ed on a series of baseless guesses. Hence, when nations eliminated God from his universe, they became vain, empty, and foolish, in their reasonings. Having shut themselves off from the only Source of light, "their senseless heart was darkened."