Abraham, the father of Judaism, Christianity, Islam and Baha'i, was eighty-five years old when he was summoned by God and told, "So Shall thy seed be." God wanted Abraham to bear a child with his seventy-six year old wife Sarah, but she instead gave Abraham her Egyptian handmaid Hagar, who bore him a son named Ishmael. God spoke to Abraham again and told him that Sarah would bear him a son who would be named Isaac, and the stage would be set for both sons of Abraham to promote God's word, but there was trouble brewing.
Tensions arose between Sarah and Hagar - Sarah wanted Hagar to leave the household, which brought grief to Abraham since he loved his first born child. Abraham pleaded to God for assistance, and God told Abraham to listen to Sarah's advice and let Hagar and son leave, but God promised Abraham that, "As for Ismael, I have heard thee. Behold, I have blessed him...and I will make him a great nation. But my covenant will I established with Issac, which Sarah shall bear unto thee at this set time..." God's plan for Isaac was elaborated in the Book of Genesis along with Isaac's descendants, but sadly, Genesis barely mentions Ishmael only that he "grew and dwelt in the wilderness and became an archer."
So what became of Ishmael? Hagar and Ishmael roamed the Arabian valley of Becca only to face starvation and death until Ishmael appealed to God for help. Hagar hurried to another location to see if God would respond. She paced back and forth from both locations seven times until an Angel responded, "What aileth thee, Hagar? Fear not, for God hath heard the voice of the lad where he is. Arise and lift up the lad and hold him in thy hand, for I will make him a great nation..." They survived and according to the Qur'an, Abraham visited Ishmael at Becca (modern day Mecca) and both were guided by God to build a sanctuary that was to be named Ka'bah and resembled a cube shaped structure that would house a holy celestial stone given to Abraham by an Angel. When the structure was completed, God told Abraham to institute a rite of the Pilgrimage to Becca (Mecca).
The problem with this account is that Isaac was promised a covenant with God while Ishmael was promised a great nation. A covenant is an unconditional spiritual contract with God and his people that assures that each side will fulfill a certain religious requirement. Ishmael's agreement with God does not involve a covenant, just merely a great nation. If God assumed that Ishmael's great nation would consume all civilizations, then God's covenant with Isaac would interfere with Ishmael's nation building because God's people would be unable to fulfill their requirements on Earth. Muhammad may have overstepped his interpretation from God about Shiria Law and global conversion to Islam. In fact, God may have tried to pacify Ishmael by providing him a section of real estate, and offering the entire kingdom, both secular and religious, to Isaac. If this is the case, then Muhammad may have broken the covenant originally ascribed to Abraham and Isaac and dictated his own terms against God's true intentions.
Source: Qur'an XXII; Tir. VII.