Sayyiduna Uqbah bin Amir (may Allah be pleased with him) said: I heard the Messenger of Allah (peace and blessings be upon him) say: "Whoever performs ablution (wudu) and performs his ablution well, then prays without heedlessness and without distraction, his sins before it are forgiven."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 14974