Sayyiduna Anas (may Allah be pleased with him) narrates that the Prophet (peace and blessings be upon him) came to a man who was taking a sacrificial animal. The Prophet (peace be upon him) said: "Ride on it." The man said: "It is a sacrificial animal." The Prophet (peace be upon him) said: "Ride on it." He again said: "It is a sacrificial animal." The Prophet (peace be upon him) said: "O unfortunate one, ride on it." («ديحك» or «ويلك» here only indicate admonition and emphasis, not a curse.)
Hadith Referenceسنن دارمي / من كتاب المناسك / 1951