'Firmness' in the Bible

These were the heads of their fathers’ households: Epher, Ishi, Eliel, Azriel, Jeremiah, Hodaviah, and Jahdiel, warriors of valor [willing and able to encounter danger], famous men, and heads of the households of their fathers.

and worthless (unprincipled, unethical) men gathered around him, useless and wicked men, who proved too strong for Rehoboam the son of Solomon when Rehoboam was young and timid, and could not assert himself against them.

And as you saw the feet and toes, partly of potter’s clay and partly of iron, it will be a divided kingdom; but there will be in it some of the durability and strength of iron, just as you saw the iron mixed with common clay.

For if indeed in the flesh I am absent, yet I am with you in spirit, rejoicing and seeing your order, and the firmness of your faith in Christ.