Here are some answers from Saint Paul in the Bible:
"Concerning Married Life

1. Now for the matters you wrote about: “It is good for a man not to have sexual relations with a woman.”
2. But since sexual immorality is occurring, each man should have sexual relations with his own wife, and each woman with her own husband.
   3 The husband should fulfill his marital duty to his wife, and likewise the wife to her husband."
   ...
   1 Corinthians 7