'Solemnly' in the Bible

Moses took the bones of Joseph with him, for Joseph had made the Israelites solemnly swear, "God will surely attend to you, and you will carry my bones up from this place with you."

The Lord said to Moses, "Go down and solemnly warn the people, lest they force their way through to the Lord to look, and many of them perish.

Moses said to the Lord, "The people are not able to come up to Mount Sinai, because you solemnly warned us, 'Set boundaries for the mountain and set it apart.'"