'Oath' in the Bible

Therefore, since he was a prophet and knew that God had promised him with an oath to put one of his descendants on his throne,

In the morning, the Jewish leaders formed a conspiracy and took an oath not to eat or drink anything before they had killed Paul.

They went to the high priests and elders and said, "We have taken a solemn oath not to taste any food before we have killed Paul.

Don't believe them, because more than 40 of them are planning to ambush him. They've taken an oath not to eat or drink before they've killed him. They are ready now, just waiting for your consent."