Here is, 1. The close application which David made of the word of God to himself: He hid it in his heart, laid it up there, that it might be ready to him whenever he had occasion to use it; he laid it up as that which he valued highly, and had a warm regard for, and which he was afraid of losing and being robbed of. God's word is a treasure worth laying up, and there is no laying it up safely but in our hearts; if we have it only in our houses and hands, enemies may take it from us; if only in our heads, our memories may fail us: but if our hearts be delivered into the mould of it, and the impressions of it remain on our souls, it is safe. 2. The good uses he designed to make of it: That I might not sin against thee. Good men are afraid of sin, and are in care to prevent it; and the most effectual way to prevent is to hide God's word in our hearts, that we may answer every temptation, as our Master did, with, It is written, may oppose God's precepts to the dominion of sin, his promises to its allurements, and his threatenings to its menaces.