9 If we ask how we are to explain this power and action of God, the principal cause, on the sacred writers we shall find that St. Jerome in no wise differs from the common teaching of the Catholic Church. For he holds that God, through His grace, illumines the writer's mind regarding the particular truth which, "in the person of God," he is to set before men; he holds, moreover, that God moves the writer's will - nay, even impels it - to write; finally, that God abides with him unceasingly, in unique fashion, until his task is accomplished. Whence the Saint infers the supreme excellence and dignity of Scripture, and declares that knowledge of it is to be likened to the "treasure" and the "pearl beyond price," since in them are to be found the riches of Christ and "silver wherewith to adorn God's house."
Source: Spiritus Paraclitus (Vatican.va)