'Steadfast' in the Bible

Then Solomon said to God, "You yourself have shown steadfast loyal love to David my father and have made me king in his place.

“O Lord God, do not turn away and reject the face of Your anointed; remember Your lovingkindness and faithfulness to Your servant David.”

So they got up early in the morning and went out into the Wilderness of Tekoa; and as they went out, Jehoshaphat stood and said, “Hear me, O Judah, and you inhabitants of Jerusalem! Believe and trust in the Lord your God and you will be established (secure). Believe and trust in His prophets and succeed.”