Harun (or Haroon) is Aaron in English. Prophet Aaron (PBUH) was Moses's eloquent brother who helped him proclaim his mission to Pharaoh. When Moses (PBUH) went to fulfill the appointment with his Lord on Mount Sinai, Aaron succeeded him in leading the Israelites. During this period a man called Al-Samiri suggested to the Israelites that they make the golden figure of a calf to worship. Thus they went astray and committed a great sin. Aaron persistently tried to convince them to return to the worship of Allah, but they did not listen to him. Upon his return, Moses was angered by the Israelites and began to re-educate them about the true religion.