Have you ever wondered why Did God reveal things figuratively in the Old Testament? Why not just reveal Christ and fullness of the economy of grace? St. Thomas Aquinas, in discussing the ceremonial precepts of the Old Law, takes up the need for figurative revelation in this way:
The things of God are not to be revealed to man except in proportion to his capacity: else he would be in danger of downfall, were he to despise what he cannot grasp. Hence it was more beneficial that the Divine mysteries should be revealed to uncultured people under a veil of figures, that thus they might know them at least implicitly by using those figures to the honor of God. (STh I-II, q. 101, a. 2, ad. 1)This follows Saint Paul's doctrine of "pedagogy" in Galatians. Humanity needed to be prepared and cultivated for the fullness of divine revelation. We reveal things to children in the same way. We don't read theological treatises to five-year-olds. We tell them about the Gospel through figures. Hymns and songs, hand signs, rote memorization, games, set prayers, etc. All of these cultivate the undeveloped mind to desire and grasp greater divine realities as they age.