In 1 Cor 1:8, the Apostle Paul speaks of how Jesus keeps believers firm in the faith until the end in order that they might be “blameless on the day of our Lord Jesus Christ.” The word translated as blameless or guiltless is the Greek adjective ἀνέγκλητος, which means not accused or without reproach.
The translation of ἀνέγκλητος into English as blameless or guiltless is potentially problematic if the word is understood by the English reader as conveying the idea of absolute moral perfection on the day of judgment. In 1 Cor 1:8, Paul does not have the absolute moral perfection of the believer in mind. Nor does he have the absolute moral perfection of Christ imputed to the believer in mind. The blamelessness in view at this point is rather a legal status on the level of covenant obedience. The covenant obedience in mind is perseverance in faith, i.e., faithfulness to the new covenant.
An examination of the use of ἀνέγκλητος elsewhere in the New Testament illustrates this. In the four other uses of this term in the New Testament (all by Paul), three of them are clearly not talking about absolute moral perfection. In 1 Tim 3:10, being ἀνέγκλητος is a moral quality that is required to be shown by a new deacon under probation. In Tit 1:6–7, being ἀνέγκλητος is a moral quality required for ordination as an elder. Elders and deacons (before the return of Christ) will never be absolutely free of personal sin; but high moral standards, and practice consistent with these standards, are required for them to be leaders in the church of Christ. The use of ἀνέγκλητος in Col 1:22 is more difficult to adjudicate. Here Paul speaks about how God has brought about our reconciliation with himself through the death of Christ “to present you holy, without blemish, and blameless before him.” Paul could have the gift of being covered in the absolute moral perfection of Christ in view at this point, however the condition of continuation in the faith that is mentioned immediately following (i.e., in Col 1:23) gives cause for considering that Paul probably has the covenant righteousness of the believer in view in Col 1:22. Surprisingly perhaps, ἀνέγκλητος does not occur in the LXX; however the use of ἀνέγκλητος in 3 Macc 5:31 by King Ptolemy IV Philopator as a description of the Jews who had been fully loyal to his ancestors is a good extrabiblical instance of ἀνέγκλητος denoting general moral goodness or loyalty.
To interpret 1 Cor 1:8 and possibly Col 1:22 as Paul expressing the need for believers to present themselves before Christ on the day of judgment as personally holy (i.e., as people who have persevered in the faith) is consistent with Paul’s teaching in Phil 1:10–11, where he prays that the Philippian Christians might know what is morally good, so as to be “pure and blameless for the day of Christ, filled with the fruit of righteousness.” It is also consistent with Paul’s teaching in 1 Thess 3:12–13, where he links abounding in love for others with God establishing “your hearts blameless in holiness before our God and Father at the coming of our Lord Jesus with all his saints.” It is also consistent with Paul’s blessing in 1 Thess 5:23, where God sanctifying the believers completely is linked with the full preservation of our spirit, soul, and body “blamelessly at the coming of our Lord Jesus Christ.” Paul’s teaching in these passages is also consistent with Peter’s teaching in 2 Pet 3:14, where, in the context of a discussion about the end of the current state of the world, Peter encourages his readers to “be diligent to be found by [God] without spot or blemish” while waiting for the new heaven and new earth, in which righteousness dwells.
The goal of the process of sanctification is cleansing with a view to the church, and all the members thereof, being made “holy and without blemish,” in order to be presented to Christ “in splendor, without spot or wrinkle or any such thing” (Eph 5:26–27). The process of sanctification can be viewed as Christ preparing his bride for the eternal marriage that will take place on the day that he arrives. Paul’s understanding is that every Christian should be morally beautiful and pleasing to the Lord on the day that he returns on analogy with the way that a bride makes herself beautiful before meeting her husband on the day of their wedding. The moral beauty of personal righteousness, cultivated through the power of God’s word and Spirit, is the blamelessness which Paul desires that all Christians will display before the Lord on the day of Christ’s return. This is the proper conceptual framework for understanding Paul’s use of ἀνέγκλητος in 1 Cor 1:8.