Abdullah bin Abbas (may Allah be pleased with them both) said: I was with my maternal aunt, Lady Maymunah (may Allah be pleased with her), when the Noble Prophet (peace and blessings be upon him) came after ‘Isha and he prayed four rak‘ahs. Then he stood up and said: "Has the boy gone to sleep?" or he said something similar. Then he stood and began to pray, so I went and stood on his left side. The Prophet (peace and blessings be upon him) took my hand and placed me on his right side.
Hadith Referenceسنن دارمي / من كتاب الصللاة / 1289
Hadith Gradingتحقیق (حسین سلیم أسد الدارانی):إسناده صحيح والحديث متفق عليه، [مكتبه الشامله نمبر: 1290]
Hadith Takhrijاس حدیث کی سند صحیح متفق علیہ ہے۔ دیکھئے: [بخاري 378] ، [مسلم 411] ، [مسند أبى يعلی 3558] و [الحميدي 1232]
Brief Explanation
(Commentary on Hadith 1288)
From this hadith, it is understood that when a person is alone, he will stand to the right side of the imam in congregational prayer (salah). And when leading two people, the imam will stand between them, with both on his sides.
Additionally, this hadith establishes the permissibility of performing prayer at home.
The Noble Prophet (sallallahu alayhi wa sallam), apart from the obligatory prayers, would mostly perform the sunnah and voluntary (nafl) prayers at home. And he (sallallahu alayhi wa sallam) said: “Pray in your homes, and do not make your homes into graveyards.”
He said this because prayer is not performed in graveyards.