عن أبي طلحة الأنصاري رضي الله عنه قال أصبح رسول الله صلى الله عليه وسلم يوما طيب النفس يرى في وجهه البشر قالوا يا رسول الله أصبحت اليوم طيب النفس يرى في وجهك البشر قال أجل أتاني آت من ربي عز وجل فقال من صلى عليك من أمتك صلاة كتب الله له عشر حسنات ومحا عنه عشر سيئات ورفع له عشر درجات ورد عليه مثلها (مسند أحمد رقم 16352)
Hadhrat Abu Talhah (Radhiallahu Anhu) relates one morning Nabi (Sallallahu Alaihi Wasallam) came to us in a state of happiness to such an extent that the joy and happiness beamed from his blessed countenance. The Sahabaah enquired: “O Rasulullah (Sallallahu Alaihi Wasallam), we notice that you are very pleased today. The happiness can be clearly seen on your blessed face.” Rasulullah (Sallallahu Alaihi Wasallam) replied, “Yes indeed a messenger came to me from my Lord with the following message, ‘Whosoever from amongst your ummah recites durood upon you once, Allah Ta’ala will record for him ten righteous deeds, wipe out and pardon ten sins, raise his rank in Jannah by ten stages and reply to his durood in a similar manner (i.e. Allah Ta’ala will send ten mercies and blessings upon him).
Add 'Salaam' to your 'Salaat' upon Rasulullah (Sallallahu Alaihi Wasallam)
Ibrahim Nasafi (Rahmatullahi Alaihi) relates: “On one occasion I had seen Rasulullah (Sallallahu Alaihi Wasallam) in a dream. I was unsure in the dream whether he was displeased with me. I stretched forth my hand, took hold of the hands of Rasulullah (Sallallahu Alaihi Wasallam) and kissed them. I asked in great anxiety, “O Rasulullah (Sallallahu Alaihi Wasallam) I am indeed one of the servants of hadith. I belong to the Ahlus Sunnah (those who follow your way) and I am a traveller from afar. Have compassion on me. Have I displeased you?” Rasulullah (Sallallahu Alaihi Wasallam) smiled and said, “Whenever you recite salaat, why do you not recite salaam?” Thereafter it became a fixed habit of mine to recite ‘wasallam’ as well. (Fazaail Durood)