Jerome
Catena Aurea · Matthäusevangelium 19
And it came to pass, that when Jesus had finished these sayings, he departed from Galilee, and came into the coasts of Judæa beyond Jordan; And great multitudes followed him; and he healed them there. The Pharisees also came unto him, tempting him, and saying unto him, Is it lawful for a man to put away his wife for every cause? And he answered and said unto them, Have ye not read, that he which made them at the beginning made them male and female, And said, For this cause shall a man leave father and mother, and shall cleave to his wife: and they twain shall be one flesh? Wherefore they are no more twain, but one flesh. What therefore God hath joined together, let not man put asunder. They say unto him, Why did Moses then command to give a writing of divorcement, and to put her away? He said unto them, Moses because of the hardness of your hearts suffered you to put away your wives: but from the beginning it was not so.
In like manner He says his wife, and not wives, and adds expressly, and they twain shall be one flesh. For it is the reward of marriage that one flesh, namely in the offspring, is made of two.