The Messenger of Allah ﷺ said, "Whoever sleeps through his daily portion of recitation, or part of it, and then recites it between the dawn prayer and the noon prayer, it will be recorded for him as though he had recited it during its proper time."
قال رسول الله ﷺ: من نام عن حزبه، أو عن شيء منه، فقرأه فيما بين صلاة الفجر وصلاة الظهر كتب له كأنما قرأه.
Muslim narrated it in "The Prayer of Travelers" (747) through several routes, from Ibn Wahb, from Yunus bin Yazid, from Ibn Shihab, from Saaib bin Yazid and Ubaydullah bin Abdullah, who both reported to him, from Abdul-Rahman bin Abdul-Qari, who said, "I heard Umar bin Khattab," and he mentioned it.His words, "from his portion", the portion (hizb) is what a person sets for himself of recitation, like a daily reading, and dividing the Quran into portions (tahzib) means apportioning it.