Sayyiduna Abu al-Tufayl (may Allah be pleased with him) said: I heard Sayyiduna Mu'adh bin Jabal (may Allah be pleased with him) say: "We went out with the Messenger of Allah (peace and blessings be upon him) on the expedition of Tabuk, and he would not set off until it had become cool; then he would combine Zuhr and Asr. Then, when evening came, he would dismount and combine Maghrib and Isha."
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 17239