The sin against the virtue of hope by apparent excess, the opposite extreme to the sin by real defect, which is despair. In presumption the excess is apparent rather than real, because it is impossible to hope too much, if by hope is meant aspiring to the good that God has promised and relying on the means that He has made available. Instead of hoping too much, one who presumes substitutes for the Christian virtue a distorted counterfeit that looks to a good or trusts in means other than those guaranteed by God's promise.
Like despair, presumption may be based upon a corruption of faith, in which case one presumes because he thinks perversely about the object or motive of hope. This is known as heretical presumption, which is a sin primarily and directly contrary to faith, rather than to hope. Such would be presumption based on the belief that God will not punish sin. In distinction to this, simple presumption, which is directly opposed to hope, supposes no false belief, but arises from a failure to make practical application to oneself of the truths known by faith.
There is a kind of presumption that is opposed to the moral virtue of magnanimity rather than to hope, as when one aspires to something humanly possible, but beyond the limits that a reasonable estimate of one's capacities should impose.
Theologians distinguish two kinds of the simple presumption opposed properly to hope. One kind is directly opposed to hope and essentially corruptive of the virtue (praesumptio contra spem ); it either rejects hope's proper motive and looks for the attainment of eternal life by one's own unaided efforts, or it expects salvation by a gift of God that would be incompatible with the divine perfections (as when one expects salvation without repentance for sin). The other kind of presumption consists in trusting beyond the limits of hope (praeter spem ), but in a way not essentially corruptive of the virtue, as when one looks rashly to God for what God could, but has not promised, to give; for example, extraordinary graces or an extended opportunity for repentance at the end of life.
Presumption directly contrary to hope is always a grave sin unless its malice is lessened by an imperfection of awareness or consent. As a sin directly opposed to a theological virtue, it is more serious, other things being equal, than a sin against a moral virtue. Because it involves a repudiation of God's plan for one's salvation, it is listed by some as a sin against the Holy Spirit. Nevertheless, it is not as grave as the sin of despair, because its affront to divine justice dishonors God less than that of despair to divine mercy, mercy being more characteristic of God than justice (St. Thomas Aquinas, Summa theologiae 2a2ae, 21.3).
Presumption of the kind called praeter spem may be seriously or venially sinful. Provided there is no serious want of submission to divine providence and no contempt of the ordinary means of salvation, it is not grievously sinful to hope for extraordinary graces or favors, although such hope is likely to be inspired by an inordinate vanity or egoism.
See Also: sin against the holy spirit; tempting god.
Bibliography: thomas aquinas, Summa theologiae 2a2ae, 21. b. h. merkelbach Summa theologiae moralis 3 v. (8th ed. Paris 1949) 1:833–837. e. vansteenberghe, Dictionnaire de théologie catholique, ed. a. vacant et al., 15 v. (Paris 1903–50) 13.1:131–135.
[p. k. meagher]
"Presumption." New Catholic Encyclopedia. . Encyclopedia.com. (August 14, 2018). http://www.encyclopedia.com/religion/encyclopedias-almanacs-transcripts-and-maps/presumption
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