On the contrary, Augustine says (Contra Faust. xxii, 36): "Christ who gave proof of God's power by teaching and reproving openly, yet not allowing the rage of His enemies to prevail against Him, nevertheless by fleeing and hiding, instructed human weakness, lest it should dare to tempt God when it has to strive to escape from that which it needs to avoid." From this it would seem that the temptation of God consists in omitting to do what one can in order to escape from danger, and relying on the assistance of God alone.
I answer that, Properly speaking, to tempt is to test the person tempted. Now we put a person to the test by words or by deeds. By words, that we may find out whether he knows what we ask, or whether he can and will grant it: by deeds, when, by what we do, we probe another's prudence, will or power. Either of these may happen in two ways. First, openly, as when one declares oneself a tempter: thus Samson (Judges 14:12) proposed a riddle to the Philistines in order to tempt them. In the second place it may be done with cunning and by stealth, as the Pharisees tempted Christ, as we read in Matt. 22:15, sqq. Again this is sometimes done explicitly, as when anyone intends, by word or deed, to put some person to the test; and sometimes implicitly, when, to wit, though he does not intend to test a person, yet that which he does or says can seemingly have no other purpose than putting him to a test.
Accordingly, man tempts God sometimes by words, sometimes by deeds. Now we speak with God in words when we pray. Hence a man tempts God explicitly in his prayers when he asks something of God with the intention of probing God's knowledge, power or will. He tempts God explicitly by deeds when he intends, by whatever he does, to experiment on God's power, good will or wisdom. But He will tempt God implicitly, if, though he does not intend to make an experiment on God, yet he asks for or does something which has no other use than to prove God's power, goodness or knowledge. Thus when a man wishes his horse to gallop in order to escape from the enemy, this is not giving the horse a trial: but if he make the horse gallop with out any useful purpose, it seems to be nothing else than a trial of the horse's speed; and the same applies to all other things. Accordingly when a man in his prayers or deeds entrusts himself to the divine assistance for some urgent or useful motive, this is not to tempt God: for it is written (2 Paralip 20:12): "As we know not what to do, we can only turn our eyes to Thee." But if this be done without any useful or urgent motive, this is to tempt God implicitly. Wherefore a gloss on Deut. 6:16, "Thou shalt not tempt the Lord thy God," says: "A man tempts God, if having the means at hand, without reason he chooses a dangerous course, trying whether he can be delivered by God."
Reply Obj. 1: Man also is sometimes tempted by means of deeds, to test his ability or knowledge or will to uphold or oppose those same deeds.
Reply Obj. 2: When saints work miracles by their prayers, they are moved by a motive of necessity or usefulness to ask for that which is an effect of the divine power.
Reply Obj. 3: The preachers of God's kingdom dispense with temporal aids, so as to be freer to give their time to the word of God: wherefore if they depend on God alone, it does not follow that they tempt God. But if they were to neglect human assistance without any useful or urgent motive, they would be tempting God. Hence Augustine (Contra Faust. xxii, 36) says that "Paul fled, not through ceasing to believe in God, but lest he should tempt God, were he not to flee when he had the means of flight." The Blessed Agatha had experience of God's kindness towards her, so that either she did not suffer such sickness as required bodily medicine, or else she felt herself suddenly cured by God. _______________________
SECOND ARTICLE [II-II, Q. 97, Art. 2]
Whether It Is a Sin to Tempt God?
Objection 1: It would seem that it is not a sin to tempt God. For God has not commanded sin. Yet He has commanded men to try, which is the same as to tempt, Him: for it is written (Malach. 3:10): "Bring all the tithes into the storehouse, that there may be meat in My house; and try Me in this, saith the Lord, if I open not unto you the flood-gates of heaven." Therefore it seems not to be a sin to tempt God.
Obj. 2: Further, a man is tempted not only in order to test his knowledge and his power, but also to try his goodness or his will. Now it is lawful to test the divine goodness or will, for it is written (Ps. 33:9): "O taste and see that the Lord is sweet," and (Rom. 12:2): "That you may prove what is the good, and the acceptable, and the perfect will of God." Therefore it is not a sin to tempt God.