Treasury of Scripture Knowledge
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.
1 Corinthians 10:1
BUT I would not that you should be ignorant, brethren, that our fathers were all under the cloud, and all passed through the sea;
For some, though they had heard, provoked him; yet not all who came out of Egypt by Moses.
LET us fear then lest, though a promise be left of entering into his rest, any one of you should appear to fail of obtaining it.
But five of them were provident, and five foolish.
1 Corinthians 10:5
Nevertheless with the most of them God was not well pleased, for they were destroyed in the wilderness.
1 Timothy 5:15
For some are already turned aside after Satan.
So we see that they could not enter in because of unbelief.