From Chapter Nine of On the Incarnation.
For that Day we have one of His own sayings to prepare us, "Get ready and watch, for ye know not the hour in which He cometh"[2] And blessed Paul says, "We must all stand before the judgment seat of Christ, that each one may receive according as he practiced in the body, whether good or ill."[3]
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Firstly, the purification state; then, the illuminative state, wherein good deeds flow from purity of heart and mind. After this state, is the unitive state, where the person is one with God at various levels, until after Death, one is united with the Beatific Vision in love and praise.
Secondly, the lives of the saints are there to help us both by example and study.
Thus united to them in the fellowship of life, he will both understand the things revealed to them by God and, thenceforth escaping the peril that threatens sinners in the judgment, will receive that which is laid up for the saints in the kingdom of heaven. Of that reward it is written: "Eye hath not seen nor ear heard, neither hath entered into the heart of man the things that God has prepared"[4] for them that live a godly life and love the God and Father in Christ Jesus our Lord, through Whom and with Whom be to the Father Himself, with the Son Himself, in the Holy Spirit, honor and might and glory to ages of ages. Amen.
This unitive state begins here, if we allow God to purify us and if we die to self.
There is no other way to see God, with purification and illumination.
Those who get stuck must pray for perseverance and the grace to continue.
To be continued...