Peter Kreeft on the First Three of Aquinas’ Quinque Viae


Arguments for God: Aquinas’ Argument from Motion

From the Summa Theologica Ia.2.3, co.

The first and more manifest way is the argument from motion. It is certain, and evident to our senses, that in the world some things are in motion. Now whatever is in motion is put in motion by another, for nothing can be in motion except it is in potentiality to that towards which it is in motion; whereas a thing moves inasmuch as it is in act. For motion is nothing else than the reduction of something from potentiality to actuality. But nothing can be reduced from potentiality to actuality, except by something in a state of actuality. Thus that which is actually hot, as fire, makes wood, which is potentially hot, to be actually hot, and thereby moves and changes it. Now it is not possible that the same thing should be at once in actuality and potentiality in the same respect, but only in different respects. For what is actually hot cannot simultaneously be potentially hot; but it is simultaneously potentially cold. It is therefore impossible that in the same respect and in the same way a thing should be both mover and moved, i.e. that it should move itself. Therefore, whatever is in motion must be put in motion by another. If that by which it is put in motion be itself put in motion, then this also must needs be put in motion by another, and that by another again. But this cannot go on to infinity, because then there would be no first mover, and, consequently, no other mover; seeing that subsequent movers move only inasmuch as they are put in motion by the first mover; as the staff moves only because it is put in motion by the hand. Therefore it is necessary to arrive at a first mover, put in motion by no other; and this everyone understands to be God.

My Own Testimony: Why Evangelism and Apologetics Can’t Be Separated From Each Other


Over the years, I have seen more than enough debates on the proper relationship between evangelism and apologetics. I have listed many of the objections I’ve heard on  college campuses.  Some say we should just preach the Gospel and not try to argue or debate with people. Other say apologetics is a form of pre evangelism. I can only speak from my own experiences. I really have never made a separation between the two and here’s why: There is no need to! I have made presentations of the Gospel and at the same time answered many objections and provided reasons for the truthfulness of the Christian faith all in one conversation. Let me give some examples from some of my evangelistic discussions  last week:

#1: Muslim conversation:

I was speaking to a Muslim in our downtown area where I live.  This Muslim was part of the group Ask a Muslim which is a…

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