“But may the God of all grace, who called us to His eternal glory by Christ Jesus, after you have suffered a while, perfect, establish, strengthen, and settle you.”
“Establish” means to fix, make fast, to set (from a prop). “Establish” then means to cause someone to become stronger in the sense of being more firm and unchanging in attitude or belief (Acts 14:22; 15:32, 41). The New Testament uses “establish” of stabilizing (i.e., the confirmation) persons. God will prop up the believer’s convictions. He will make firm the faith of the tottering believer.
“But I have prayed for you, that your faith should not fail; and when you have returned to Me, strengthen your brethren” (Luke 22:32).
In the previous verse (5:9), Peter uses the word “steadfast” for dealing with the Devil with a strong faith system. Paul desired to visit Rome that the saints might be “established” in their faith,
“For I long to see you, that I may impart to you some spiritual gift, so that you may be established” (Romans 1:11).
“Now to Him who is able to establish you according to my gospel and the preaching of Jesus Christ, according to the revelation of the mystery kept secret since the world began but now has been made manifest, and by the prophetic Scriptures has been made known to all nations, according to the commandment of the everlasting God, for obedience to the faith–to God, alone wise, be glory through Jesus Christ forever. Amen” (Romans 16:25-27).
Paul commanded the Corinthians to stand strong in their faith,
“Watch, stand fast in the faith, be brave, be strong” (1 Corinthians 16:13).
Timothy sought to strengthen the faith of the believers at Thessalonica,
“Therefore, when we could no longer endure it, we thought it good to be left in Athens alone, and sent Timothy, our brother and minister of God, and our fellow laborer in the gospel of Christ, to establish you and encourage you concerning your faith, that no one should be shaken by these afflictions; for you yourselves know that we are appointed to this” (1 Thessalonians3:1-3).
One of the works of God is to confirm the hearts of the saints,
“Night and day praying exceedingly that we may see your face and perfect what is lacking in your faith? Now may our God and Father Himself, and our Lord Jesus Christ, direct our way to you. And may the Lord make you increase and abound in love to one another and to all, just as we do to you, so that He may establish your hearts blameless in holiness before our God and Father at the coming of our Lord Jesus Christ with all His saints” (1 Thessalonians 3:10-13).
“Now may our Lord Jesus Christ Himself, and our God and Father, who has loved us and given us everlasting consolation and good hope by grace, comfort your hearts and establish you in every good word and work” (2 Thessalonians 2:16- 17).
“For this reason I will not be negligent to remind you always of these things, though you know and are established in the present truth” (2 Peter 1:12).
James exhorts Christians to “establish” their hearts in the light of the coming of Christ,
“You also be patient. Establish your hearts, for the coming of the Lord is at hand” (James 5:8).
The character of this confirmation may be learned from its use in the hearts of the saints.
“Now it came to pass, when the time had come for Him to be received up, that He steadfastly set His face to go to Jerusalem” (Luke 9:51).
There is an onus both upon God and upon us to strengthen our faith.
God will not allow us to waver in our faith if we develop our faith. He will fix us firm and make us stable in what we believe. God will Himself make us steady if we have positive volition toward His work on our faith system.
God will put the Christian upon a solid foundation of faith. Christian faith is not transitory or temporary but solid as granite when we allow God to develop it. Athletes who discipline themselves with rigorous training develop toughness of fiber and staying power. Believers who seriously expand their faith will develop a tough certitude that is full of confidence and stability.