The Muslim line is a direct descendant of Ishmael whose mother was Hagar. Hagar was a servant of Abraham who was given permission to sleep with by his wife Sarah. She and Abraham knew of the promise God had told them about a child one day but Sarah disobeyed and allowed Abraham to have a child with Hagar. Previously, God promised Abraham that his descendants would be as numerous as the stars and he kept that promise with Ishmael as well. Even though God had his line already planned, He still blessed Hagar and Ishmael however the prophetic line was only allowed through Abraham and Sarah's child Isaac, who they had later. God's chosen people have followed through the lineage of Abraham, Isaac, and Jacob which later begat King David which later begat Joseph and Mary. This is why the Muslim of today claim the promised land of Israel too.
They feel they are entitled too it since Abraham was given the blessing however the Bible is clear which line was to receive the blessings and that is through Isaac. As for Muhammad, he wasn't a biblical prophet and isn't mentioned in any prophecy. He is a self proclaimed "prophet" without any thing to back it up. You and I might as well claim the same status as he because it would carry the same weight. Absolutely nothing.
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