Sorry for the delay. Doing chores in between answering.
So your question is, how do I explain these verse in relation to salvation? humm, my first thought is do these verses suggest the saved are not saved? Matt. 24 is Jesus describing the end of the age. Matt: 25 is the parable of the 10 virgins and Rev 14 describes the Lamb and the 144,000. These are often related to end times discussions, which this is not, but you have worked it in to the discussion of salvation.
Do these verses say that the saved are not saved? No they don't. Matt 24:13 describes the nature of the saved to endure. Matt 25:10 is a parable of 10 virgins which there where some foolish ones who where not prepared. I guess the thought you may have is that those who are secure in their salvation are foolish and just do what they want. However, that's not the case.
No one says "hey your saved so party and sin", but for some reason that's the message to those who are not sure when it comes to this.
Knowing your salvation is to believe. Security in that knowledge of belief is by faith and a relationship with God.
I would say that those who do not know they are saved or can't know for sure are dealing with some sort of guilt they harbor about something in their past, or present that is keeping them from a relationship with God. I can't know what that might be.
Listen, I was a strong willful sinner who did not believe in God and never cared about it. I'll put my former willful sinful life against anyone's here.
like the blind man, all I can say is that I was blind and now I see. I have no desire to go back to being blind.
I do not worry about loosing my salvation. I know where it is. It's in Christ and he's where he's always been even when I was far away from him. He's tested me plenty and will continue. I'm done. I've died. I only live in Christ.
As for the end times. I don't bother with that junk. I don't need to. can't wait if it to happens in my life time. I welcome it. I don't care if I'm killed this afternoon or 99 years from now. This life is not about me.