Hebrews 10:39

But we are not of those who draw back to perdition; but of those who believe to the saving of the soul.

Luke 17:31-32

In that day, let not him that is on the house-top, and whose goods are in the house, come down to take them away. Likewise, he that is in the field, let him not turn back.

Acts 15:38

But Paul did not think it proper to take with them him who had departed from them from Pamphylia, and did not go with them to the work.

2 Timothy 4:10

for Demas has forsaken me, having loved the present age; and he has gone to Thessalonica, Crescens to Galatia, Titus to Dalmatia.

Treasury of Scripture Knowledge

Summary

Because they turned back from him, and would not consider any of his ways:

Bible References

Turned

Luke 17:31
In that day, let not him that is on the house-top, and whose goods are in the house, come down to take them away. Likewise, he that is in the field, let him not turn back.
Acts 15:38
But Paul did not think it proper to take with them him who had departed from them from Pamphylia, and did not go with them to the work.
2 Timothy 4:10
for Demas has forsaken me, having loved the present age; and he has gone to Thessalonica, Crescens to Galatia, Titus to Dalmatia.
Hebrews 10:39
But we are not of those who draw back to perdition; but of those who believe to the saving of the soul.