Summa Theologica

ARTICLE IV. — WHETHER DIVINATION WHICH IS PERFORMED THROUGH THE INVOCATIONS OF DEMONS IS ILLICIT.

To the fourth point, one proceeds thus: 1. It seems that divination which is performed through the invocations of demons is not illicit. For Christ committed nothing illicit, according to that saying (I Peter ii, 22): Who did no sin. But the Lord asked the demon: What is thy name? who answered: Legion, for we are many, as is contained (Mark v, 9). Therefore, it seems that it is lawful to ask a demon about something hidden.

2. Furthermore, the souls of the saints do not favor those who inquire illicitly. But to Saul, inquiring about the outcome of a future war from a woman having a spirit of python, Samuel appeared and foretold the future outcome to him, as is read (I Kings xxviii). Therefore, divination which is performed through interrogation by demons is not illicit.

3. Furthermore, it seems to be lawful to seek the truth from someone who knows it, when it is useful to know it. But it is sometimes useful to know certain hidden things, which can be known through demons, as appears in the discovery of thefts. Therefore, divination which is performed through the invocation of demons is not illicit.

But contrary to this is what is said (Deuteronomy xviii, 10): Neither let there be found among you any one that consults soothsayers, or that consults spirits of python.

CONCLUSION. — Divination which is performed through the express invocation of demons is entirely illicit.

I answer that it must be said that every divination which is performed through the invocations of demons is illicit, for a double reason. The first of which is taken from the part of the principle of divination, which is the pact expressly made with the demon through the very invocation of the demon (2) Here Blessed Thomas seems to speak specifically of express invocation, for the first reason, as Sylvius says, is taken from the part of the principle of divination, which is a pact expressly made with the demon through the very invocation of the demon. (3) When there is an express invocation, it is always a mortal sin; if, however, it were only tacit, the sin could be only venial; therefore, this circumstance must be declared in confession., and this is entirely illicit: whence it is said against some (Isaiah xxviii, 15): You have said: We have entered into a league with death, and we have made a covenant with hell; and it would be still graver if sacrifice or reverence were exhibited to the invoked demon. The second reason is taken from the part of the future event. For the demon, who intends the perdition of men, even if he sometimes tells the truth through such responses of his, intends to accustom men to believe him; and thus he intends to lead them into something which is harmful to human salvation. Whence Athanasius, expounding that which is contained (Luke iv): He rebuked him, saying: Hold thy peace, says: "Although the demon confessed the truth, Christ nevertheless checked his speech, lest he proclaim his own iniquity together with the truth: so that he might also accustom us not to care for such things, even if he seems to speak the truth. For it is wicked that, when divine Scripture is present to us, we should be instructed by the devil."

To the first, therefore, it must be said that, as Bede says (Luke viii), upon that: What is thy name? "The Lord does not inquire as if ignorant; but so that, once the plague which He was tolerating had been confessed, the power of the healer..."