Worship only Allah alone

This hadith is about how Prophet Muhammad (PBUH) cursed the Jews and Christians for taking the graves of their prophets as places of worship. This is considered a form of idolatry, known as shirk in Arabic, which is strictly forbidden in Islam. Taking graves or any other physical object as a place to pray or seek help from is an act that goes against Islamic teachings. It also shows disrespect to those who are buried there by treating them like gods instead of humans. The Prophet's curse was meant to remind people not to fall into this type of idolatrous behavior and instead focus on worshipping Allah alone.