In 12:13-14 we have the writer's concluding word.
The writer's intention is to lead men to fear God that God may eventually show them His New Testament economy concerning the producing of His church, the Body of Christ, which consummates in the New Jerusalem as God's eternal enlargement and expression (v. 13).
God will judge men in this age for their deeds, even every secret thing, according to good or evil, and at His great white throne for their eternal destiny (v. 14; Rev. 20:11-15).