“(Which he had promised afore by his prophets in the holy scriptures,)”
King James Version (KJV)
1:2 Which he promised before - Of old time, frequently, solemnly. And the promise and accomplishment confirm each other. #De 18:18|; Isa 9:6,7; 53:1; 61:1; Jer 23:5.
Ro 1:2 Which he had promised before, etc. This gospel was no innovation, but a fulfillment of God's long-cherished plans, and had been promised through the prophets of the Old Testament. Indeed the Old Testament is a system of types, shadows and promises pointing forward to the coming of Christ. "Of him have all the prophets borne witness" (Ac 10:43).