'Confident' in the Bible

I am not ashamed of the gospel, for it is the power of God for salvation [from His wrath and punishment] to everyone who believes [in Christ as Savior], to the Jew first and also to the Greek.

And art confident that thou thyself art a guide of the blind, a light of them which are in darkness,

This righteousness of God comes through faith in Jesus Christ for all those [Jew or Gentile] who believe [and trust in Him and acknowledge Him as God’s Son]. There is no distinction,

and endurance, proven character (spiritual maturity); and proven character, hope and confident assurance [of eternal salvation].