Ruling on entering the mosque for rest and sleep

His final question is: Is it permissible to enter the mosque and sit in it without praying until the adhan is called? I ask for your guidance. May Allah reward you with the best reward.
Answer: There is nothing wrong with entering the mosque and sitting in it for rest or sleep, such as taking a nap or the like. There is nothing wrong with that. Some of the Companions used to sleep in the mosque during the time of the Prophet (peace and blessings be upon him). However, he should not sit... It is not befitting for him to sit except after the greeting prayer, if he is in a state of ritual purity. If he is in a state of wudu, he should pray two rak'ahs and then sit. As for if he is not in a state of ritual purity, there is no blame on him; he may sit, and praise be to Allah. There is no blame in that.