Why are the "saints" describes as, not those with just faith, but those who have faith AND keep the commandments of God (Rev 14:12, 12:17)?
I dont usually deal with "end time" Theology as im a Teaching Evangelist who is a musician.
So, my prime directive, is to reach unbelievers with the Gospel and teach new or "fuzzy" believers how to believe right and get grown up, spiritually.
But, because you asked me, i'll give you a very basic understanding, regarding your verses, so that you can realize that your question is not related to accurate end time understanding.
We, are currently in "the time of the Gentiles'. This is why we are given the Righteousness of God, as "Grace Through Faith"
Paul is our teacher as he is the "Gentile Apostle".
God's Grace, is the "free gift of Salvation"....given to "as many as will Believe".. John 3:16 .... Salvation is a Gift, not earned, and not kept.
Salvation is : "The Gift of Righteousness". This means that God on the Cross took the responsibility of saving us, during the time of the Gentiles.
In other words God Himself took full responsibility to get us into heaven. We give him our faith and God takes it from there. God is Faithful to complete our salvation, Himself. Philippians 1:6
This will end.
This offer of "Grace" and "the GIFT of Salvation"... Its going to end.
The GIFT OFFER is going to stop being offered.
When?
During the Great Trib.
In that time, you have a different setup. You have to believe and you have to endure.
Its a faith + Works.........to be saved and to Stay saved.
Those are your verses.