Once having beed saved, it is impossible for the elect of God to lose their salvation. The children of God are called to live in complete obedience to him, by his grace, out of thankfulness for their salvation, and they are to persevere in this obedience to the end. God has chosen his children before the foundation of the world and has written their names in His book of life. Never is their faith a condition of their salvation, and never can they go lost. They will forever be God's children, and will continue in faith until their end of everlasting joy in the new heavens and new earth.
Perseverance of the Saints is part of the Five Points of Calvinism and is represented by the letter P in the word TULIP:
The last of the Five Points of Calvinism is represented by the letter P in the word TULIP and is the doctrine of the perseverance of the saints. This doctrine deals with the question whether those who are once brough to faith and salvation will continue in faith and in that salvation to the very end, in other words, whether those who once believe will finally and surely go to heave...
A. The Name—there are three different names used for this doctrine:
1. The perseverance of the saints: The name used in the Canons of Dorbt, the original Five Points of Calvinism, is "the perseverance of the saints." This name, as we shall see, emphasizes the responsibility of every believe to continue to "persevere" in faith and holiness.
2. The preservation of saints: Many Calvinists prefer to speak of "the preservation of the saints" because this name emphasizes the same thing that the other point emphasizes, that is, the sovereignty of God in salvation and the truth that salvation is all of grace from beginning to end. This name, then, teaches the truth that God "preserves" all those whom He has chosen and redeemed and in whose hearts He has worked by the power of His irresistible grace.
3. Eternal Security: The third name that is used for this doctrine is "eternal security." This emphasizes the comfort that believers receive from the doctrine: that they are secure in their salvation, not only through this life but into eternity.
This name, while not in itself objectionable, is often used by those who believe "once saved, always saved," no matter how a person lives or what he does. That teaching, as we hope to show, is not biblical, and if we use the name "eternal security," we must be sure to contradict that teaching. We may not believe that the assurance of final salvation allows anyone to live carelessly and wickedly...
When we speak of the perseverance or preservation of saints, we are teaching the truth that those who are saved persevere to the end as a result of the grace of God, not as a result of their own strength or works, but always in the way of real, personal holiness.
The name "saints", when it is applied to believers is a name that refers to their holiness. The name means holy ones. it is ver important for our study that that word is included. We do not believe just in perseverance or preservation, but in the perseverance of saints. It is important, first of all, because it reminds us of the real issue. The question raised by this doctrine is not simply whether or not the Bible teaches that a person once saved is always saved, but also what the Bible teaches about saints.
The Bible, however, shows that saints are holy only by the grace of God, that of themselves they are sinners and have no natural holiness or power to be holy. It is God who makes saints.