Scripture, like revelation, is an organic whole that has gradually come into being; the mature plant was already enclosed in the seed, the fruit was present in the germ. Revelation and Scripture both kept pace with the state of the church, and vice versa. For that reason one can never draw conclusions for the present based on conditions prevailing in the church in the past. Granted, the church before Moses was without Scripture, and before the completion of revelation the church was never in possession of the whole Bible. But this does not prove anything for the dispensation of the church in which we now live, one in which revelation has ceased and Scripture is complete. For this dispensation Scripture is not only useful and good but also decidedly necessary for the being (esse) of the church.
Reformed Dogmatics Vol. 1: Prolegomena (Grand Rapids, Michigan; Baker Academic; 2003) p. 471.