John Chrysostom
Catena Aurea · Matthäusevangelium 5
For I say unto you, That except your righteousness shall exceed the righteousness of the Scribes and Pharisees, ye shall in no case enter into the kingdom of heaven. Ye have heard that it was said by them of old time, Thou shalt not kill; and whosoever shall kill shall be in danger of the judgment: But I say unto you, That whosoever is angry with his brother without a cause shall be in danger of the judgment: and whosoever shall say to his brother, Raca, shall be in danger of the council: but whosoever shall say, Thou fool, shall be in danger of hell fire.
By righteousness is here meant universal virtue. But observe the superior power of grace, in that He requires of His disciples who were yet uninstructed to be better than those who were masters under the Old Testament. Thus He does not call the Scribes and Pharisees unrighteous, but speaks of their righteousness. And see how even herein He confirms the Old Testament that He compares it with the New, for the greater and the less are always of the same kind.