'Strengthen' in the Bible

But I have prayed for thee, that thy faith fail not: and when thou art converted, strengthen thy brethren.

But the God of all grace, who hath called us unto his eternal glory by Christ Jesus, after that ye have suffered a while, make you perfect, stablish, strengthen, settle you.

Be watchful, and strengthen the things which remain, that are ready to die: for I have not found thy works perfect before God.