Sayyiduna Harith bin Malik (may Allah be pleased with him) used to make announcements among the people during the days of Hajj. Sufyan says: To the best of my knowledge, he narrated this statement. The Noble Prophet (peace and blessings of Allah be upon him) said: "Whoever swears an oath and thereby unlawfully takes the wealth of a Muslim, when he appears before Allah Almighty, Allah will be angry with him."