Shiniki no Mahoutsukai ~Shin ni Aisareta Rakudaisei wa Mahou Gakuin e Kayou~神域の魔法使い～神に愛された落第生は魔法学院へ通う～; The Divine Mage: The God-Beloved Dropout Enters the Magic Academy

He was a sorcerer from the divine realm, a master of magic who introduced revolutionary new theories. On the verge of death, he cast a reincarnation spell and was reborn years later. Now living as Lucien, the son of a farmer, he discovers a world where the common sense of his past life no longer applies—a world where magical technology has drastically declined――?!