We proceed to the ninth article thus:

1. It seems that to believe is not meritorious. It was said in 12ae, Q.114, Art.4, that the principle of merit is charity. Now faith is a preamble to charity, just as nature is a preamble. But a natural action is not meritorious, since we merit nothing by our natural powers. Neither then is the act of faith meritorious.

2. Again, belief is a mean between opinion and science, or the study of what is known scientifically. Now the study of science is not meritorious, and neither is opinion. Neither, then, is it meritorious to believe.

3. Again, he who assents to anything by faith either has a sufficient reason for believing, or does not. If he has a sufficient reason, his assent is no credit to him, since he is not then free to believe or not to believe. If he does not have a sufficient reason, he believes lightly, in the manner referred to in Ecclesiasticus 19:4: "he that believes in haste is light in heart" -- which does not appear to be meritorious. Hence in no wise is it meritorious to believe.

On the other hand: it is said in Heb.11:33: "Who through faith . . . obtained promises." Now this would not have been, had they not merited by believing. To believe is therefore meritorious.

I answer: as we said in 12ae, Q.114, Arts.3 and 4, our actions are meritorious in so far as they proceed from the free will as moved by God through grace. It follows that any human action which depends on the free will can be meritorious, provided that it is related to God. Now "to believe" is the act of the intellect as it assents to divine truth at the command of the will as moved by God through grace. It is therefore an act commanded by the free will as ordered to God. The act of faith can therefore be meritorious.

On the first point: nature is related to charity, which is the principle by which we merit, as matter is related to its form. Faith, on the other hand, is related to charity as a disposition is related to the ultimate form which it precedes. Now it is obvious that a subject, or matter, cannot act except by the power of its form. Neither can a preceding disposition act before its form is received. Once the form has been received, however, a subject and a preceding disposition alike act by the power of the form, and the form is the main principle of action. The heat of a fire, for example, acts by the power of its substantial form. Thus without charity, neither nature nor faith can produce a meritorious action. But when charity supervenes, the act of faith becomes meritorious through charity, just as a natural action thereby becomes meritorious, including a natural action of the free will.

On the second point: two things may be considered in regard to science, namely, the assent of the knower to what he knows, and his study of it. The assent of one who knows scientifically does not depend on his free will, since the cogency of demonstration compels him to give it. Hence in science, assent is not meritorious. The actual study of a scientific matter, however, does depend on his free will, since it lies within his power whether to study or not to study. The study of science can therefore be meritorious if it is referred to the end of charity, that is, to the honour of God, or to the service of one's neighbour. In faith, on the other hand, both assent and practice depend on the free will. The act of faith can therefore be meritorious in both respects. Opinion does not involve firm assent. It is indeed feeble and infirm, as the philosopher says in Post. An., text 44. Hence it does not appear to proceed from a complete volition, nor, therefore, to have much of the nature of merit in respect of its assent, although it may be meritorious in respect of actual study.

On the third point: he who believes has a sufficient reason for believing. He is induced to believe by the authority of divine teaching confirmed by miracles, and what is more, by the inward prompting of divine invitation. Hence he does not believe lightly. But he does not have a reason such as would suffice for scientific knowledge. Thus the character of merit is not taken away.