'Ought' in the Bible

Then Abimelech called Abraham and said to him, “What have you done to us? And how have I sinned against you, that you have brought on me and on my kingdom a great sin? You have done to me things that ought not to be done.”

Now the sons of Jacob came in from the field when they heard it; and the men were grieved, and they were very angry because he had done a disgraceful thing in Israel by lying with Jacob’s daughter, for such a thing ought not to be done.