It is narrated from Sayyiduna Abu Malik al-Ash'ari (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) used to say: "Purification is half of faith; 'al-hamdu lillah' (praise be to Allah) fills the Scale (with reward); 'subhan Allah' (glory be to Allah) and 'Allahu akbar' (Allah is the Greatest) fill what is between the earth and the heavens; fasting is a shield; patience is light; charity is a proof; and the Qur'an will be a proof either for you or against you. Every person sells his soul, either freeing it or destroying it."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الطهارة / 185