VII. However, although he was free from the slavery of sin (because created just and upright) still he was not free from mutability (because whatever his holiness and righteousness, he was mutable, from which in consequence he could fall). Adam was placed in such a state in which he could stand and fall, sin and not sin. Although this argues less perfection than the state of grace (which is immutable), still it denotes no fault or imperfection (since immutability is by no means a gift of nature, but of grace). Still that mutability cannot belong to the liberty of Adam (although sometimes it is so termed) because that condition did not fear to be adorned with so illustrious a description which placed a limit to both the liberty and happiness of man; rather it was only an appendage of the Adamic liberty, so proper to it that it neither has been nor can be in any other man.
FRANCIS TURRETIN, Institutes of Elenctic Theology, ed. James T. Dennison Jr., trans. George Musgrave Giger, vol. 1 (Phillipsburg, NJ: P&R Publishing, 1992–97), 8.1.7 (p. 571).