"Be watchful, stand firm in the faith, act like men (andrizomai), be strong" (1 Corinthians 16:13). This four-part command builds to its climax in andrizomai — embodying faith with courageous action. The Old Testament background is Joshua's command: "Be strong and courageous" (Joshua 1:6-9, using the Hebrew chazaq). For Paul, spiritual maturity involves not just right doctrine but courageous living — the willingness to stand firm when pressures demand compromise.
Andrizomai comes from aner (man/adult male) and means to act with manly courage — to be brave, to take heart. It is Paul's direct command to the Corinthians in one of Scripture's most compact calls to courage.