When we were trying to create a game for schools we removed the few religious proverbs because we figured that could hurt our chances. It is delicate to present this kind of proverb still keeping the humor, but not being disrespectful. This one is from the Hadith-an Islamic proverb. A good teacher could generate a discussion about the meaning and wisdom of this proverb.
"Trust in God, but ----------- your camel.
"Tie" is the right answer.