Abū ʿAbdallāh Muḥammad ibn Muḥammad ibn Ahmad Ibn Juzayy al-Kalbi (1321 - 1357) (in Arabic, محمد بن محمد بن أحمد بن عبد الله بن يحيى بن يوسف بن عبد الرحمن بن جزي الكلبي الغرناطي) was a scholar, writer of poetry, history, and law from Al-Andalus. He is also known as the writer who dictated the travels of Ibn Battuta. He was the son of Abú-l-Qásim Muhammad Ibn Juzayy (the panegyrist of Abú-l-Hayyáy Yúsuf of Granada) who died in the Battle of Rio Salado in 1340.
Ibn Juzayy wrote the Rihla of Ibn Battuta in 1352-55. It is clear that Ibn Juzayy outright copied some long passages (like the description of Medina from the Rihla of Ibn Jubayr and the description of Palestine by Mohammed al-Abdari al-Hihi) and used information from books from his own library.
He wrote many religious works such as his Qawanin al-Fiqhiyyah or "The Laws of Jurisprudence"  a comparative manual of the jurisprudence of the five Sunni madhhabs (Maliki, Hanafi, Shafi`i, Hanbali, Dhahiri) with emphasis on the Maliki school. He is also famous for his tafsir of the Qur'an, his book on legal theory "Aqrab al-Wusool `ala `Ilm al-Usool" or "The Nearest of Paths to the Knowledge of the Fundamentals of Islamic Jurisprudence," as well as his treatise on Sufism based on the Qur'an, "The Refinement of the Hearts." One of his teachers was Ibn Rushd al-Saghir, the grandson of Averroes and author of Bidiyat al-Mujtahid.
He died in Fez in 1357 two years after the completion of the Rihla of Ibn Battuta.
Ibn Juzayy, Muhammad ibn Ahmad, Tasfiyat al-qulub fi al-wusul ila hadrat 'Allam al-Ghuyub / li-Ibn Juzayy al-Gharnati ; dirasat wa-tahqiq Munir al-Qadiri Bu Dashish ; taqdim Ahmad al-Tawfiq. al-Tab'ah 1. [Casablanca : s.n.], 1998 ISBN 9981-1951-0-3
M. Isabel Calero Secall, RULERS AND QĀDĪS: THEIR RELATIONSHIP DURING THE NASRID KINGDOM, in: Journal Islamic Law and Society, Volume 7, Number 2 / June, 2000
Ibn al-Khatib, al-Ihata fi akhbar Gharnata, ed. M. Inan, 4 vols. (Cairo, 1973-77), I, 157-62;
Ibn al-Khatib, al-Katiba al-kamina, ed. Ihsan Abbas,(Beirut, 1983), 138-43
Ibn al-Khatib, al-Lamha al-badriyya fi l-dawla al-nasriyya, ed. Muhibb al-Din al-Khatib, 3rd ed. (Beirut, 1978), 116-18
Al-Maqqari Nafh al-tib min ghusn al-Andalus al-ratib, ed. I. 'Abbas, Beirut, 1968, t. 8, pp. 40-54
F.Velazquez Basanta, Retrato jatibiano de Abu Bakr Ya'far Ahmad ibn Yuzayy, otro poeta y qadi al-yama'a de Granada. Anales de la Universidad de Cadiz, IX-X (1992-93), 39-51
Maria Arcas Campoy, Un tratado de derecho comparado: el Kitàb al-Qawànìn de Ibn Juzayy, pp. 49-57, In: Atti del XIII Congresso dell'Union Européenne d'Arabisants et d'Islamisants (Venezia 1986)he was the one who Ibn Battuta dedicated his life and works to.