Be mindful of your prayers and take extra care when you are uncertain or doubtful of your actions during them.

This hadith is about prayer and how to handle doubt during it. The Prophet Muhammad ﷺ taught that if someone has any doubts while praying, they should make two prostrations after giving the salutation. This means that once a person has finished their prayer and said the final salutations, they should bow down twice more as an extra precaution to ensure that their prayer was valid. This teaches us to be mindful of our prayers and take extra care when we are uncertain or doubtful of our actions during them.