It is narrated from Sayyiduna Salman (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: "Indeed, when the believing servant stands for prayer, his sins are placed upon his head, then they scatter from him just as the clusters of a date palm scatter to the right and the left."
Hadith Referenceالمعجم الكبير للطبراني / باب السين / 6063