“Jesus saith unto them, Did ye never read in the scriptures, The stone which the builders rejected, the same is become the head of the corner: this is the Lord's doing, and it is marvellous in our eyes?”
King James Version (KJV)
21:42 The builders - The scribes and priests, whose office it was to build up the Church. Is become the head of the corner - Or the chief corner stone: he is become the foundation of the Church, on which the whole building rests, and is the principal corner stone, for uniting the Gentiles to it, as the chief corner stone of a house supports and links its two sides together. #Psalm 118:22|.
Mt 21:42 The stone which the builders rejected. "The Scripture" that speaks of this stone is Ps 118:22,23--a psalm which the Jews applied to the Messiah. Peter twice applied it to him (Ac 4:11 1Pe 2:7). The figure represents a stone rejected by the builders as worthless, and then found to be the chief corner-stone of the building. The stone is Christ, rejected by the Jewish nation, but "the chief corner-stone", for this is what is meant by the "head of the corner". The "corner-stone" joined two walls. Alford thinks this is a reference to the union of Jews and Gentiles in the church. Marvellous. That the rejected stone should become the "chief corner-stone, elect and precious", on which the whole structure of the spiritual temple rests (1Pe 2:6 Isa 28:16).