Sayyiduna Abdul-Rahman bin Azhar (may Allah be pleased with him) said: In the year of Hunayn I saw the Prophet (peace and blessings be upon him) asking about the mount of Sayyiduna Khalid bin al-Walid (may Allah be pleased with him). When they reached the place Jadha', a drinker was brought. He (peace and blessings be upon him) said: "Beat him." So the people beat him with their hands, with sandals and with garments, and also threw dust on him. Then he (peace and blessings be upon him) said: "Rebuke him." Later, Sayyiduna Abu Bakr al-Siddiq (may Allah be pleased with him) gave 40 lashes during his caliphate, and Sayyiduna Umar al-Faruq (may Allah be pleased with him), on the advice of the Companions (may Allah be pleased with them), fixed it at 80 lashes.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الأشربة والحد فيها / 17537