No, it's the once faithful who become unfaithful and recant their faith who do not secure salvation.
Jesus Christ is the One that has secured salvation for us for all those that come to & believed in Him are saved.
Not the issue under contention.
But it is when you consider who the vessels unto dishonor that are vessels of wood & earth, that did not depart from iniquity, but still in His House.
2 Timothy 2:18 Who concerning the truth have erred, saying that the resurrection is past already; and overthrow the faith of some. 19 Nevertheless the foundation of God standeth sure, having this seal, The Lord knoweth them that are his. And, let every one that nameth the name of Christ depart from iniquity. 20 But in a great house there are not only vessels of gold and of silver, but also of wood and of earth; and some to honour, and some to dishonour. 21 If a man therefore purge himself from these, he shall be a vessel unto honour, sanctified, and meet for the master's use, and prepared unto every good work.
So when a believer in works that deny Him ( Titus 1:16 ) , He will deny them ( 2 Timothy 2:12 ) for being workers of iniquity ( Matthew 7:21-23 ), but yet even if we believe not, He is faithful for He abides ( 2 Timothy 2:13 )
it is what we build on that foundation that shall be judged, but that foundation is not going anywhere 21 Corinthians 3:10-17 and nether is that seal of adoption Ephesians 4:30 which is why we are to call even former believers and not just carnal believers to depart from iniquity before the Bridegroom comes or else they will be weeping and gnashing of teeth for missing out on the firstfruits of the resurrection as Esau did in giving up his birthright for a meal.
Hebrews 12:15 Looking diligently lest any man fail of the grace of God; lest any root of bitterness springing up trouble you, and thereby many be defiled; 16 Lest there be any fornicator, or profane person, as Esau, who for one morsel of meat sold his birthright. 17 For ye know how that afterward, when he would have inherited the blessing, he was rejected: for he found no place of repentance, though he sought it carefully with tears.
2 Corinthians 5:7 (For we walk by faith, not by sight 8 We are confident, I say, and willing rather to be absent from the body, and to be present with the Lord. 9 Wherefore we labour, that, whether present or absent, we may be accepted of him. 10 For we must all appear before the judgment seat of Christ; that every one may receive the things done in his body, according to that he hath done, whether it be good or bad. 11 Knowing therefore the terror of the Lord, we persuade men; but we are made manifest unto God; and I trust also are made manifest in your consciences.