Catena Aurea on Matthew 5:20–22: Augustine of Hippo

This expression, the kingdom of heaven, so often used by our Lord, I know not whether any one would find in the books of the Old Testament. It belongs properly to the New Testament revelation, kept for His mouth whom the Old Testament figured as a King that should come to reign over His servants. This end, to which its precepts were to be referred, was hidden in the Old Testament, though even that had its saints who looked forward to the revelation that should be made.