Genesis 2:18-24Revised Standard Version (RSV)
18 Then the Lord God said, “It is not good that the man should be alone; I will make him a helper fit for him.” 19 So out of the ground the Lord God formed every beast of the field and every bird of the air, and brought them to the man to see what he would call them; and whatever the man called every living creature, that was its name. 20 The man gave names to all cattle, and to the birds of the air, and to every beast of the field; but for the man there was not found a helper fit for him. 21 So the Lord God caused a deep sleep to fall upon the man, and while he slept took one of his ribs and closed up its place with flesh; 22 and the rib which the Lord God had taken from the man he made into a woman and brought her to the man. 23 Then the man said,
24 Therefore a man leaves his father and his mother and cleaves to his wife, and they become one flesh.
Mark 10:2-9Revised Standard Version (RSV)
2 And Pharisees came up and in order to test him asked, “Is it lawful for a man to divorce his wife?” 3 He answered them, “What did Moses command you?” 4 They said, “Moses allowed a man to write a certificate of divorce, and to put her away.” 5 But Jesus said to them, “For your hardness of heart he wrote you this commandment. 6 But from the beginning of creation, ‘God made them male and female.’ 7 ‘For this reason a man shall leave his father and mother and be joined to his wife,[a] 8 and the two shall become one flesh.’ So they are no longer two but one flesh. 9 What therefore God has joined together, let not man put asunder.”