Sunan Ibn Majah, Book 4, Hadith 40 (In-Book) ⓘ
It was narrated that Abu Hurairah said: "The Messenger of Allah said: 'When one of you performs ablution and does it well, then he comes to the mosque with no other motive but prayer and not seeking anything other than the prayer, he does not take one step but Allah raises him in status one degree thereby, and takes away one of his sins, until he enters the mosque. When he enters the mosque he is in a state of prayer so long as he is waiting for the prayer.'"
حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا أَبُو مُعَاوِيَةَ، عَنِ الأَعْمَشِ، عَنْ أَبِي صَالِحٍ، عَنْ أَبِي هُرَيْرَةَ، قَالَ قَالَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ " إِذَا تَوَضَّأَ أَحَدُكُمْ فَأَحْسَنَ الْوُضُوءَ ثُمَّ أَتَى الْمَسْجِدَ لاَ يَنْهَزُهُ إِلاَّ الصَّلاَةُ لاَ يُرِيدُ إِلاَّ الصَّلاَةَ لَمْ يَخْطُ خَطْوَةً إِلاَّ رَفَعَهُ اللَّهُ بِهَا دَرَجَةً وَحَطَّ عَنْهُ بِهَا خَطِيئَةً حَتَّى يَدْخُلَ الْمَسْجِدَ فَإِذَا دَخَلَ الْمَسْجِدَ كَانَ فِي صَلاَةٍ مَا كَانَتِ الصَّلاَةُ تَحْبِسُهُ " .
also referenced under: Hadith 774 (Reference) & Volume 1, Book 4, Hadith 774 (DarusSalam)