'Stedfast' in the Bible

and Israel seeth the great hand with which Jehovah hath wrought against the Egyptians, and the people fear Jehovah, and remain stedfast in Jehovah, and in Moses His servant.

And the hands of Moses are heavy, and they take a stone, and set it under him, and he sitteth on it: and Aaron and Hur have taken hold on his hands, on this side one, and on that one, and his hands are stedfast till the going in of the sun;