It is narrated from Sayyiduna Abbas (may Allah be pleased with him) that he and Sayyiduna Abu Sufyan (may Allah be pleased with him) were with the Prophet (peace and blessings be upon him). The Prophet (peace and blessings be upon him) delivered a sermon and said, "Now the fierce battle has begun." And he said, "Call out: O companions of Surah Al-Baqarah."