Yet in this thing ye did not believe the LORD your God,
2 Chronicles 20:20
And they rose early in the morning, and went forth into the wilderness of Tekoa: and as they went forth, Jehoshaphat stood and said, Hear me, O Judah, and ye inhabitants of Jerusalem; Believe in the LORD your God, so shall ye be established; believe his prophets, so shall ye prosper.
Because they believed not in God, and trusted not in his salvation:
Yea, they despised the pleasant land, they believed not his word:
And the head of Ephraim is Samaria, and the head of Samaria is Remaliah's son. If ye will not believe, surely ye shall not be established.
Take heed, brethren, lest there be in any of you an evil heart of unbelief, in departing from the living God.
And to whom sware he that they should not enter into his rest, but to them that believed not?
So we see that they could not enter in because of unbelief.
I will therefore put you in remembrance, though ye once knew this, how that the Lord, having saved the people out of the land of Egypt, afterward destroyed them that believed not.