"إذا توضأ أحدكم فأحسن الوضوء ثم خرج إلى المسجد ¤ لا ينزعه إلا الصلاة لم تزل رجله اليسرى تمحو عنه سيئة وتكتب له اليمنى حسنة حتى يدخل المسجد ولو يعلم الناس ما في العتمة والصبح لأتوهما ولو حبوا"
The Prophet (peace and blessings be upon him) said:
"When one of you performs ablution and does it very well, then goes out to the mosque, and nothing but the intention of prayer brings him out (of his house), his left foot keeps wiping away a sin from him and his right foot keeps writing a good deed for him until he enters the mosque. And if people knew how much reward there is in the Isha and Fajr prayers, they would surely come to them, even if they had to come crawling on their knees."
Hadith Referenceصحیح الجامع الصغیر / حرف الألف / 441