Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
suyuti:22827a – Kaʿb b. ʿUjrah

[Machine] "Whoever reads {Say, "He is Allah, [who is] One"} three times in a night or day, it is as if he has recited the entire Quran."  

السيوطي:٢٢٨٢٧a – عن كعب بن عجرة

"مَنْ قَرَأَ فِي لَيلَة أَوْ يَوْم {قُلْ هُوَ اللَّهُ أَحَدٌ} ثَلاثَ مَرَّاتٍ كَانَ مقْدَارَ القُرآنِ".  

ابن النجار عن كعب بن عجرة

See similar narrations below:

Collected by Suyūṭī
suyuti:22835a –
Request/Fix translation

  

السيوطي:٢٢٨٣٥a –

"مَنْ قَرَأَ {قُلْ هُوَ اللَّهُ أَحَدٌ} فَكَأَنَّمَا قَرَأَ ثلُثَ القُرآنِ".  

أَبو عبيد، [حم] أحمد [ن] النسائي وابن منيع ومحمد بن نصر، [قط] الدارقطنى في السنن في الأَفراد وابن مردويه، [ض] ضياء المقدسي في مختاره عَنْ أُبيّ بن كعب