Hebrews 6:4

6:4 For it is impossible in the case of those who have once been enlightened, tasted the heavenly gift, become partakers of the Holy Spirit,

Hebrews 10:2

10:2 For otherwise would they not have ceased to be offered, since the worshipers would have been purified once for all and so have no further consciousness of sin?

Hebrews 11:15

11:15 In fact, if they had been thinking of the land that they had left, they would have had opportunity to return.

Hebrews 13:23

13:23 You should know that our brother Timothy has been released. If he comes soon, he will be with me when I see you.