We are as saved as we choose to be. For God's part - we are eternally secure. When we become Born Again we do not lose our free will. Thus we can wander away from Christ to the point that we could deny Him and no longer choose to believe - The Truth.

 Take heed, BROTHERS, lest there be in any of you an evil heart of unbelief, in DEPARTING from the living God. 13(warning) But exhort one another daily, while it is called Today; lest any of you become hardened through the deceitfulness of sin. 14For WE are made partakers of Christ, IF.... we hold the beginning of our confidence steadfast (endure) to the end; (Hebrews 3:12-14)

For it is impossible for those who were ONCE enlightened, and have tasted of the heavenly gift, and were MADE PARTAKERS of the Holy Ghost, 5And have tasted the good word of God, and the powers of the world to come, 6If they SHALL FALL WAY, (were there to begin with)  to renew them AGAIN unto repentance; (already repented) seeing they crucify to themselves the Son of God afresh, and put him to an open shame. 

(Hebrews 6:4-6)

All in the church are not The Bride -

 

If you are Born Again you have been made "worthy" of - heaven. Not all believers are faithful in their "betrothal" to Christ. Not all keep themselves unspotted, without wrinkle and blameless and not all are filled with the Spirit (Ready) when Christ comes for them - either at death or The Rapture. Not all choose to deny themselves, pick up their crosses and follow Christ - He is not their FIRST love. Therefore - They are not "worthy" of Him. (His Bride) The Rapture is an event for The Bride to be taken out..... Those who are not the Bride become tribulation saints. 

 Don't be misled--you cannot mock the justice of God. You will always harvest what you plant.

Galatians 6:7