You would invite the brother to the deen by explaining the fundamentals to him example the Shahadah the 5 pillars of Islaam and the 6 artickes/tenants of faith. Your main goal is to get him to embrace Islaam before the angel of death comes for his soul. May Allah guide the brother to Islaam upon the Quran and the and the correct Aqeedah and Menhaj Ameen
May Allah give him hidayat and embrace to Islam
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