Those God has accepted in the Beloved, effectually called and sanctified by his Spirit, and given the precious faith of his elect can neither totally nor finally fall from a state of grace. They will certainly persevere in grace to the end and be eternally saved, because the gifts and callings of God are irrevocable. Therefore, he still brings about and nourishes in them faith, repentance, love, joy, hope, and all the graces of the Spirit that lead to immortality (Jn 10:28-29; Php 1:6; 2Ti 2:19; 1Jn 2:19). Even though many storms and floods arise and beat against them, yet these things will never be able to move the elect from the foundation and rock to which they are anchored by faith. The felt sight of the light and love of God may be clouded and obscured from them for a time through their unbelief and the temptations of Satan (Ps 89:31-32; 1Co 11:32). Yet God is still the same; they will certainly be kept by the power of God for salvation, where they will enjoy their purchased possession. For they are engraved on the palms of his hands, and their names have been written in the book of life from all eternity (Mal 3:6).
This perseverance of the saints does not depend on their own free will but on the unchangeableness of the decree of election (Ro 8:30; 9:11, 16), which flows from the free and unchangeable love of God the Father. It is based on the efficacy of the merit and intercession of Jesus Christ and union with him (Ro 5:9-10; Jn 14:19), the oath of God (Heb 6:17-18), the abiding of his Spirit, the seed of God within them (1Jn 3:9), and the nature of the covenant of grace (Jer 32:40). The certainty and infallibility of their perseverance is based on all these things.
They may fall into grievous sins and continue in them for a time, due to the temptation of Satan and the world, the strength of corruption remaining in them, and the neglect of means of their preservation (Mt 26:70, 72, 74). In so doing, they incur God’s displeasure and grieve his Holy Spirit (Isa 64:5, 9; Eph 4:30); their graces and comforts become impaired (Ps 51:10, 12); their hearts are hardened and their consciences wounded (Ps 32:3-4); they hurt and scandalize others and bring temporary judgments on themselves (2Sa 12:14). Nevertheless, they will renew their repentance and be preserved through faith in Christ Jesus to the end (Lk 22:32, 61-62).