Musnad Ahmad

It is narrated from Hazrat Safwan bin Mu'attal (may Allah be pleased with him) that he submitted to the Noble Prophet (peace and blessings be upon him): O Messenger of Allah! I want to ask you a question about which you have knowledge and I am unaware, and that is: which are the times during the day and night in which you consider prayer to be disliked? The Noble Prophet (peace and blessings be upon him) said: When you have performed the Fajr prayer, then refrain from prayer until the sun rises. When the sun has risen, then perform prayer, for at that time the angels are present and it is accepted, until the sun is directly overhead like a spear above you. When that happens, that is the hour in which Hell is kindled and its doors are opened, until it declines from your right side. When that happens, then perform prayer, for at that time too the angels are present and it is accepted, until you have performed the Asr prayer.