It is narrated from Sulayman bin Yasar that he said: I was standing by Sayyiduna Abu Hurayrah (may Allah be pleased with him) while he was performing ablution, when Ibn Abbas (may Allah be pleased with them both) also arrived. He said: O Ibn Abbas! Do you know why I have performed ablution? He said: No. Abu Hurayrah (may Allah be pleased with him) said: I ate pieces of cheese. Ibn Abbas (may Allah be pleased with them both) said: I do not care why you performed ablution. By Allah! I saw the Messenger of Allah (peace and blessings be upon him) eat bread and meat, then he (peace and blessings be upon him) stood up for the prayer but did not perform ablution.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الطهارة / 732