Daniel 3

We learn that some of the hateful Chaldeans came to Nebuchadnezzar and complained that -

"...certain Jews whom thou hast set over the affairs of the province of Babylon, Shadrach, Meshach, and Abed-nego; these men, O king, have not regarded thee: they serve not thy gods, nor worship the golden image which thou hast set up." (Daniel 3:12)

"Then Nebuchadnezzar in his rage and fury commanded to bring Shadrach, Meshach, and Abed-nego. Then they brought these men before the king.

14 Nebuchadnezzar spake and said unto them, Is it true, O Shadrach, Meshach, and Abed-nego, do not ye serve my gods, nor worship the golden image which I have set up?

15 Now if ye be ready that at what time ye hear the sound of the cornet, flute, harp, sackbut, psaltery, and dulcimer, and all kinds of musick, ye fall down and worship the image which I have made; well: but if ye worship not, ye shall be cast the same hour into the midst of a burning fiery furnace; and who is that God that shall deliver you out of my hands?

16 Shadrach, Meshach, and Abed-nego, answered and said to the king, O Nebuchadnezzar, we are not careful to answer thee in this matter.

17 If it be so, our God whom we serve is able to deliver us from the burning fiery furnace, and he will deliver us out of thine hand, O king.

18 But if not, be it known unto thee, O king, that we will not serve thy gods, nor worship the golden image which thou hast set up."  (Daniel 3:13–18)

The faith of these me is obvious, even to the point if they were not saved, they would remain obedient.