I answer that, Fear is a movement of the appetitive power. Now it belongs to the appetitive power to pursue and to avoid, as stated in Ethic. vi, 2: and pursuit is of good, while avoidance is of evil. Consequently whatever movement of the appetitive power implies pursuit, has some good for its object: and whatever movement implies avoidance, has an evil for its object. Wherefore, since fear implies an avoidance, in the first place and of its very nature it regards evil as its proper object.
It can, however, regard good also, in so far as referable to evil. This can be in two ways. In one way, inasmuch as an evil causes privation of good. Now a thing is evil from the very fact that it is a privation of some good. Wherefore, since evil is shunned because it is evil, it follows that it is shunned because it deprives one of the good that one pursues through love thereof. And in this sense Augustine says that there is no cause for fear, save loss of the good we love.
In another way, good stands related to evil as its cause: in so far as some good can by its power bring harm to the good we love: and so, just as hope, as stated above (Question [40], Article [7]), regards two things, namely, the good to which it tends, and the thing through which there is a hope of obtaining the desired good; so also does fear regard two things, namely, the evil from which it shrinks, and that good which, by its power, can inflict that evil. In this way God is feared by man, inasmuch as He can inflict punishment, spiritual or corporal. In this way, too, we fear the power of man; especially when it has been thwarted, or when it is unjust, because then it is more likely to do us a harm.
In like manner one fears "to be over another," i.e. to lean on another, so that it is in his power to do us a harm: thus a man fears another, who knows him to be guilty of a crime lest he reveal it to others.
This suffices for the Replies to the Objections.