Turretin: Leviticus 18:5 Is Clear Proof Of The Covenant Of Works

VII. Second, a law was imposed upon Adam, which necessarily implies a federal agreement and contract. For he who receives it, binds himself officially to obedience under the punishment denounced through the same; he who gives it (for the very reason that he exacts obedience) is bound to furnish indemnity and security to the one obeying. Although Moses sets forth only one part of that federal sanction (referring to punishment, Gen. 2:17), still he proves that the former concerning the promise should not be excluded, both from the sacrament of the tree of life (by which it was sealed) and from the threatening of death (which by reason of contraries had the implied promise of life and from the various passages of Scripture which express more clearly the nature and sanction of the law, as Lev. 18:5—“If a man do these, he shall live in them,” cf. Dt. 27:26; Ezk. 20:11; Mt. 19:17; Gal. 3:12)

Francis Turretin, Institutes of Elenctic Theology, ed. James T. Dennison Jr., trans. George Musgrave Giger, vol. 1 (Phillipsburg, NJ: P&R Publishing, 1992–97), 8.3.7 [pp. 575–76].