It is narrated from Sayyiduna Qubath bin Ashyam al-Laythi (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "The prayer of two men, in which one leads the other, is purer in the sight of Allah than the separate prayer of four men; and the prayer of four men, in which one of them leads them, is purer in the sight of Allah than the separate prayer of eight men; and the prayer of eight men, in which one of them leads them, is purer in the sight of Allah than the separate prayer of a hundred men."
Hadith Referenceالمعجم الكبير للطبراني / باب القاف / 16123