Riyad as-Salihin 1075
Ibn 'Umar (May Allah be pleased with them) reported:
The Messenger of Allah (ﷺ) said, "Islam is based on five (pillars): testifying that there is no true god except Allah and that Muhammad (ﷺ) is His slave and Messenger; performing of Salat (Iqamat-as-Salat); the payment of Zakat; performing Hajj (pilgrimage) to the House [of Allah (Ka'bah)] ; and Saum (fasting) during the month of Ramadan." [Al-Bukhari and Muslim] .
وعن ابن عمر رضي الله عنهما قال‏:‏ قال رسول الله صلى الله عليه وسلم‏:‏ ‏
"‏ بني الإسلام على خمس‏:‏ شهادة أن لا إله إلا الله وأن محمدًا رسول الله، وإقام الصلاة، وإيتاء الزكاة، وحج البيت، وصوم رمضان‏"‏ ‏(‏‏(‏متفق عليه‏)‏‏)‏‏.‏