Justification in the Old Testament

"The faith of the fathers was grounded on Christ who was to come, as ours is on Christ who has now come. Different times do not change faith, nor the Holy Spirit, nor his gifts. There has been, there is, and there will always be one mind, one judgment and understanding concerning Christ, in the ancient fathers and in believers today and in the future."

Luther, Galatians, p. 137.