Sayyiduna Anas (may Allah be pleased with him) said: The people were alarmed, so the Prophet (peace and blessings be upon him) rode a slow horse belonging to Sayyiduna Abu Talhah (may Allah be pleased with him). Then he (peace and blessings be upon him) set out, spurring it on. The people also came after him (peace and blessings be upon him), and he (peace and blessings be upon him) said: "Do not be alarmed; this (horse) is a veritable sea."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الشهادات / 20849