حَدَّثَنَا عَبْدُ اللهِ بْنُ يَزِيدَ، قَالَ: حَدَّثَنَا عَبْدُ الرَّحْمَنِ بْنُ زِيَادٍ قَالَ لِي عَبْدُ اللهِ بْنُ يَزِيدَ: سَمِعْتُ عَبْدَ اللهِ بْنَ عَمْرٍو، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ: أَسْرَعُ الدُّعَاءِ إِجَابَةً دُعَاءُ غَائِبٍ لِغَائِبٍ.
'Abdullah ibn 'Amr reported that the Prophet, may Allah bless him
and grant him peace, said, "The swiftest supplication to be answered is
the supplication of someone for another person who is not present."
Safwan ibn 'Abdullah ibn Safwan, who was married to the daughter
of Abu'd-Darda', said, "I visited them in Syria and found Umm ad-Darda'
in the house, but not Abu'd-Darda'. She asked, 'Are you intending to go
on hajj this year?' 'Yes,' I replied. She said, 'Make supplication to Allah
and ask for good for us. The Prophet, may Allah bless him and grant him
peace, said, "The supplication of a Muslim man for his absent brother is
answered. At his head there is a guardian angel. Whenever he asks Allah
to give his brother good, the angel says, 'Amen, and may you have the same.'"'
I met Abu'd-Darda' in the market and he said something similar which was
related from the Prophet, may Allah bless him and grant him peace."