In his tenth sermon on the thirteenth chapter of 1 Corinthians (aka, Charity and Its Fruits: “Grace Tends to Holy Practice”), Jonathan Edwards preaches to his congregation that God’s “practical” purpose in his saving work is to make his people holy in their practice.
Election, redemption, and effectual calling are all so that God’s people will live holy lives. So it is with spiritual knowledge and understanding:
A true knowledge of God and divine things is a practical knowledge.
As to a speculative knowledge of things of religion, there are some wicked men who have attained to great measures of it.
Men may be men of vast learning, and their learning may consist very much in their knowledge in divinity, their knowledge of Scripture, and other things appertaining to religion, and they may be able to reason very strongly about the attributes and works of God, and doctrines of Christianity; but herein their knowledge fails of being a saving knowledge, that it is only a speculative and not a practical knowledge.
He who has a right and saving acquaintance with divine things sees the excellency of holiness, and of all the ways of holiness, for he sees the beauty of God which consists in holiness.
And so he sees the hatefulness of the ways of sin.
And if a man knows the hatefulness of the ways of sin, certainly this tends to his avoiding those ways. And if he sees the loveliness of the ways of holiness, this tends to incline him to walk in them.
He who knows God sees him to be worthy to be obeyed. (pp. 296-7 in the Yale-Works)