It is narrated from Sayyiduna Zayd bin Khalid al-Juhani (may Allah be pleased with him) that whoever performs ablution well and prays two rak'ahs in which there is no heedlessness (sahw), his previous sins are forgiven. This hadith is sahih (authentic) on the condition of Imam Muslim; there is no defect in it that would weaken it, but the two Shaykhs did not record it.