It is narrated from Sayyiduna Abdullah bin Amr (may Allah be pleased with them both) that indeed the Messenger of Allah (peace and blessings be upon him) said: "The prayer that is accepted the quickest is the prayer of an absent person for another absent person."
Hadith Referenceمسند الشهاب / 1330
Hadith Gradingمحدثین:إسناده ضعيف
Hadith Takhrij«إسناده ضعيف ، وأخرجه أبو داود : 1535 ، والترمذي : 1980 ، الادب المفرد : 623» عبدالرحمٰن بن زیادضعیف ہے ۔
Brief Explanation
Benefit: Safwan bin Abdullah bin Safwan, in whose marriage was Darda bint Abi Darda, narrates that I came to my in-laws in the land of Sham (Syria), and I found Umm Darda at home but did not find Abu Darda. Umm Darda said to me: "Do you intend to perform Hajj this year?" I said: "Yes." She said: "Pray to Allah for good for us as well, because the Prophet sallallahu alayhi wa sallam used to say: 'Indeed, the supplication of a Muslim servant for his brother in his absence is accepted. At his head is appointed an angel; whenever he supplicates for good for his brother, the angel says: Ameen, and for you the same.'" Safwan says that after this I met Abu Darda in the market, and he said the same, and narrated this hadith of the Prophet sallallahu alayhi wa sallam. [مسلم : 2733 ، الادب المفرد : 625]