Why did Moses agree to save the Israelites?

Answer 1

Moses was himself an Israelite, although brought up in Pharaoh's household. So, when it came to a choice, he went with his own oppressed people rather than the Egyptians. This did not seem like a wise choice at the time, however, Moses was evidently a man of faith. Since his faith was in a true and living God, it had something concrete on which to stand, even though Moses himself certainly had his faults.

Whatever ideas we may have, whether it be a desire for unity with his blood relations or anything else, the Book of Hebrews gives the biblical verdict:

24By faith Moses, when he was come to years, refused to be called the son of Pharaoh's daughter; 25Choosing rather to suffer affliction with the people of God, than to enjoy the pleasures of sin for a season;

Answer 2

Moses supported the Hebrews because he was a Hebrew himself. In his infancy, his mother sent him adrift into the Nile River (historically and geologically correct) because the Pharoah issued a command to kill all the Hebrew boys. Therefore, in order to save Moses, his mother sent him into the river (Exodus ch.2) in the hope that another family would take him as their own and raise him to fill God's prophecy.

Answer 3

Because God commanded them to. See Numbers ch.9, verse 15-20.