It is narrated from Sayyiduna Ruwayfi' bin Thabit (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: "Whoever sends blessings upon Muhammad (peace and blessings be upon him) and makes this supplication: 'Allahumma anzilhu al-maq'ad al-muqarraba 'indaka yawm al-qiyamah' (O Allah, grant him the seat of those brought near to You on the Day of Resurrection), my intercession becomes binding for him."
Imam al-Tabarani (may Allah have mercy on him) said: "This hadith is narrated from Sayyiduna Ruwayfi' (may Allah be pleased with him) only with this chain; Ibn Lahi'ah is alone in narrating it."
Hadith Referenceالمعجم الأوسط / باب الباء / 3285
Hadith Takhrij«أخرجه أحمد فى «مسنده» برقم: 17265، والبزار فى «مسنده» برقم: 2315، والطبراني فى «الكبير» برقم: 4481، 4480»