It is narrated from Silah bin Ashyam (may Allah have mercy on him) that the Messenger of Allah (peace and blessings be upon him) said: "Whoever prays a prayer during which not even a thought of anything of worldly affairs passes through his heart and mind, then whatever he asks of Allah, the Mighty and Majestic, during that prayer, Allah, Glorified and Exalted, will surely grant it to him."
Imam Ahmad narrated this hadith in Kitab al-Zuhd, and its chain is mursal, since Silah bin Ashyam (may Allah have mercy on him) is an eminent Successor who narrated it directly from the Prophet (peace and blessings be upon him); however, there are supporting reports for it in other reliable hadith regarding presence of heart and humility in prayer.
Hadith Referenceالمطالب العالية بزوائد المسانيد الثمانية / كتاب النوافل / 670
Hadith Gradingمحدثین:إسناده حسن، مرسل
Hadith Takhrij«حکم الحدیث المطالب العالیہ محققاً تنسیق د. سعد بن ناصر بن عبد العزيز الشَّثري- مکتبہ شاملہ :مرسل، إسناده حسن لغيره. » «أورده ابن حجر فى "المطالب العالية"، 670، وأخرجه ابن أبى شيبة فى «مصنفه» برقم: 7713»