Abdullah bin Shaqiq says that one day after Asr, Sayyiduna Ibn Abbas (may Allah be pleased with them both) addressed (the people), until the sun set and the stars appeared. People began saying: The prayer! The prayer! A man from Banu Tamim came, saying without stopping: The prayer! The prayer! So he said: May you have no mother! Will you teach me the Sunnah? Then he said: I saw the Prophet (peace and blessings be upon him) combining Zuhr and Asr, and Maghrib and Isha. Abdullah bin Shaqiq says: Something troubled me in my heart, so I went to Sayyiduna Abu Hurayrah (may Allah be pleased with him) and asked him, and he (may Allah be pleased with him) also confirmed what he had said.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 5553