"[Some] say, ‘The sleepers were three, and their dog made four,’ others say, ‘They were five, and the dog made six’– guessing in the dark– and some say, ‘They were seven, and their dog made eight.’ Say [Prophet], ‘My Lord knows best how many they were.’ Only a few have real knowledge about them, so do not argue, but stick to what is clear, and do not ask any of these people about them."
(Surah Kahf: Verse 22)
This is a beautiful reminder from Allah Almighty in Quran. This is a verse about the people of cave. Allah Almighty is telling that people argue about the exact number of people and their dog in the cave. As that time there were no written scriptures so this incident of cave was told orally. Therefore, different things were being told about the people of cave. So Allah Almighty is in fact forbidding us to not go into these details. What we should focus upon is the lesson being taught through this story of people of cave. We should keep this in mind that just as these people of cave slept for so many years in the same way, we will also be resurrected one day. So we should strive for good deeds. That's why Allah Almighty has not told about the exact number of the people because He wants us to focus on the lesson not on the extra details which are of no use. This gives us another lesson that we should not ask so many irrevalent questions about the shariah. We should do what we have been told and we should not get into such irrevalent questions. We should not corrupt the basic skeleton of Islam rather we should stick to what we are told.
May Allah forgive us and make us His obedient servants.