The attempt to put to the test or make trial of one or more of God's attributes, such as His knowledge, will, power, or wisdom. This testing of God can be made by word, deed, or omission. One can, for example, ask God to perform a miracle when, judging by the ordinary standards of prudence, it is not called for. It was to induce Christ to tempt God in this way that the devil suggested to Him that He cast Himself down from the pinnacle of the Temple in the expectation that God would preserve Him from harm (Mt 4.6). Similarly, it is tempting God for anyone to expect miraculous protection while neglecting the immediate and obvious ways of protecting oneself that divine providence has already provided. The expectation or hope, however, must be inordinate to amount to a tempting of God, for to ask of Him something within the ordinary course of divine providence or humbly to petition Him to grant even an extraordinary favor is not to tempt God but to honor Him by demonstrating trust in His omnipotence and mercy. The same can be said of the act of one who, moved by genuine divine inspiration, requests God to do something out of the ordinary but needed for a good purpose, as when, for example, certain saints asked God to perform miracles to help them in their apostolic work. Moreover, to be a tempting of God, a divine attribute must be put to the test, i.e., one must ask or expect God to do something. It is not tempting God to act imprudently or rashly with no expectation of God's intervention.
Theologians distinguish two kinds or degrees of tempting God. It is formal when one says or does something with the express or explicit intention of putting God on trial. In this case it makes no difference whether the testing proceeds from incredulity, as when one positively doubts the existence of a divine attribute, or whether it arises from presumption, as when one who firmly believes in the power of God exposes himself to danger of death to see whether God wants to save him. On the other hand, the tempting is virtual (implicit, interpretative) when one does not have the express intention of testing God but acts in such a way that a miracle or other extraordinary effect seems to be expected from Him.
Tempting God is condemned in the Scriptures (see Dt 6.16; Ps 77.18, 19.56; Mt 4.7). The formal or explicit tempting of God is a mortal sin, because it is an insult to God to question His attributes and to challenge Him to manifest them. It is a sin principally against the virtue of religion, which demands that due reverence and worship be given to God. It may also involve a sin against faith, e.g., when God is put to the test because some doctrine of faith is doubted. The virtual or implicit tempting of God may be a venial sin if God is recklessly tempted only in a slight matter or if there is not enough advertence to the intrinsic seriousness of the action.
Bibliography: thomas aquinas, Summa Theologiae 2a2ae, 97. r. brouillard, Dictionnaire de théologie catholique, ed. a. vacant, 15 v. (Paris 1903–50; Tables générales 1951–) 15.1:116–127. p. palazzini, Dictionary of Moral Theology, 1211–12. d. m. prÜmmer, Manuale theologiae moralis (Freiburg-Barcelona 1955) 2:526–528. h. davis, Moral and Pastoral Theology (New York 1958) 2:31–32. l. g. fanfani, Manuale theoricopracticum theologiae moralis 3 v. (Rome 1950–51) 3:110–112.