Charles H. Spurgeon on Psalms 90:12

Apply our hearts unto wisdom. Moses speaketh of wisdom as if it were physic, which doth no good before it be applied; and the part to apply it to is the heart, where all man's affections are to love it and to cherish it, like a kind of hostess. When the heart seeketh it findeth, as though it were brought unto her, like Abraham's ram. Therefore God saith, "They shall seek me and find me, because they shall seek me with their hearts", Jer 29:13; as though they should not find him with all their seeking unless they did seek him with their heart. Therefore the way to get wisdom is to apply your hearts unto it, as if it were your calling and living, to which you were bound aprentices. A man may apply his ears and his eyes as many truants do to their books, and yet never prove scholars; but from that day when a man begins to apply his heart unto wisdom, he learns more in a month after than he did in a year before, nay, than ever he did in his life. Even as you see the wicked, because they apply their hearts to wickedness, how fast they proceed, how easily and how quickly they become perfect swearers, expert drunkards, cunning deceivers, so if ye could apply your hearts as thoroughly to knowledge and goodness, you might become like the apostle which teacheth you. Therefore, when Solomon sheweth men the way how to come by wisdom, he speaks often of the heart, as, "Give thine heart to wisdom", "let wisdom enter into thine heart", "get wisdom", "keep wisdom", "embrace wisdom", Pr 2:10 4:5 8:8, as though a man went a wooing for wisdom. Wisdom is like God's daughter, that he gives to the man that loves her, and sueth for her, and means to set her at his heart. Thus we have learned how to apply knowledge that it may do us good; not to our ears, like them which hear sermons only, nor to our tongues, like them which make table talk of religion, but to our hearts, that we may say with the virgin, "My heart doth magnify the Lord", Lu 1:46, and the heart will apply it to the ear and to the tongue, as Christ saith, "Out of the abundance of the heart the mouth speaketh," Mt 12:34. —Henry Smith.