It is narrated from Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Whoever makes a supplication in which there is neither (anything of) sin nor the severing of family ties, Allah Almighty will certainly grant him in return for it one of three things: either He forgives through it some sin of his that has passed, or He fulfils it for him quickly in this world, or He stores it up for him in the Hereafter."
Hadith Referenceالمعجم الأوسط / باب العين / 4368
Hadith Takhrij«أخرجه الحاكم فى «المستدرك» برقم: 1822، وأحمد فى «مسنده» برقم: 11302، وأبو يعلى فى «مسنده» برقم: 1019، وعبد بن حميد فى «مسنده» برقم: 937، وابن أبي شيبة فى «مصنفه» برقم: 29780، والطحاوي فى «شرح مشكل الآثار» برقم: 882، والطبراني فى «الصغير» برقم: 1022 م»