Full Assurance (πληροφορία)
Full assurance is a combination of πληροω ("to fill where lacking") and φερω ("to bear up"), conveying a state of complete and unwavering confidence. Consequently, "full assurance" represents a profound and complete certainty. The term plerophoria (πληροφορία) specifically refers to this profound and comprehensive confidence in one's faith, understanding, and the promises of God—without doubt or hesitation.
Paul highlights the full assurance the Thessalonians possessed in the gospel, which came to them not only in word but also with inherent ability and by the Holy Spirit (1 Thessalonians 1:5). They fully bore the gospel message in their own lives, knowing that it was the truth. All those who believed in Macedonia and Achaia knew how in the face of tribulation the Thessalonians turned from idols to worship the living God.
In Colossians 2:2, Paul expresses his desire for the Christians to know what agony he has over the saints in Colossi and Laodicea. He shares his agony so that their hearts are encouraged and knit together in love, attaining to a full assurance of understanding, unto a full experiential knowledge of the mystery from God—the Christ. In Christ dwells the fullness of the Godhead bodily and we are complete in Him. Therefore, we are not to let anyone cheat us through philosophy and empty deceit to live by the traditions of men according to the basic principles of the world system and not according to Christ.
While correcting and encouraging the Jews who embraced Christ, who predominantly still lived in Jerusalem, Paul expresses his confidence in them and the things accompanying their salvation. Rather than growing in the Christian faith, they went back to being zealous for the law. However, once a person has tasted of the heavenly gift, they cannot again be renewed unto a change of mind, as salvation has already taken place and brought about transformation. Therefore, they need to move on from the basic principles of the Christ to maturity, leaving behind the dead works from the law. God is not unjust to forget our work and labor of love. Our faith in God’s word will not be in vain. Thus, we are to be diligent to remain in our full assurance of hope until the end, not become sluggish in our Christian life (Hebrews 6:11).
Because we have a High Priest—Jesus the resurrected One—we have full assurance of faith to draw near to God with a true heart. Drawing near to God requires faith in His word (Hebrews 11:6). With this in mind, let us stir each other up in love, holding fast to our verbal agreement concerning the gospel of Christ without wavering, for the One who promised is faithful (Hebrews 10:22). Through law, no one could become mature; however, through Christ’s sacrifice for sin, we are brought to our intended end, maturity, under a new covenant. Therefore, let us not forsake the assembling of each other while exhorting one another as the day approaches.