Sayyiduna Mihjan (may Allah be pleased with him) said: I prayed Zuhr - or Asr - in my house, then went out to the mosque and found the Messenger of Allah (peace and blessings be upon him) sitting with people around him, so I sat with them. Then the prayer was established, and the Messenger of Allah (peace and blessings be upon him) went inside and led the people in prayer. Then he came out and found me sitting in the same place where he had left me, and said: "Are you not a Muslim?" I said: "Of course, O Messenger of Allah, I am a Muslim." He (peace and blessings be upon him) said: "What prevented you from coming inside and praying with the people?" I said: "I have already prayed in my house." The Messenger of Allah (peace and blessings be upon him) said: "When you have prayed in your house, then come to the mosque and find the people praying, pray with them as well."
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 17832