True believers possess eternal life by faith (1 John 5:13) but Scripture does warn believers about departing from the living God in unbelief, drawing back into perdition, making Christ of no effect, to no profit, falling from grace, (Heb. 3:12; 10:38,39; Gal. 5:1-4) - which denial is the only thing one can and must take credit for.
But the problem with most Catholics is that they never had a "Scriptural day of salvation," and as explained, "salvation by grace" means that "by the grace of God" they actually become good enough to be with God via (for most) baptism without personal faith and repentance, and thru RC Purgatory. About which I have said much already in refutation.
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