The single biggest threat to "serious Christians" or "Devout Catholics" is this.
We really think our "walk with Christ" makes us better than all those other folk who are not walking with Christ, but who are simply wandering about and bumping into things.
Take for example, two women.
One is very religious and makes frequent devotions and is certain that she is never in the wrong - because, well for one thing she's so darned and deliberately Good.
Another has fallen from the faith - and from other things - promiscuous, a bit of a mess on the inside, has been around the block once or twice and is probably even now somewhere in the alley trying to find her way home.
You'll find when the Trial comes, that the first can not be trusted. But the second will die for you.
And, really, for Him.