'Vigorous' in the Bible

sound and beyond reproach in instruction, so that the opponent [of the faith] will be shamed, having nothing bad to say about us.

I have written to you, fathers, because you know Him who has existed from the beginning. I have written to you, young men, because you are strong and vigorous, and the word of God remains [always] in you, and you have been victorious over the evil one [by accepting Jesus as Savior].

Dear friends, although I was eager to write to you about the salvation we share, I found it necessary to write to you and urge you to continue your vigorous defense of the faith that was passed down to the saints once and for all.