Galatians 6:9 says, 'Let us not grow weary in…' what?

Answer: Doing good

Let us not grow weary in well-doing, for in due time we will reap a harvest if we do not give up.

“Let us not grow weary in well-doing, for in due time we will reap a harvest if we do not give up.”— Galatians 6:9 (BSB)