Radhiallahu Anhu is an honorific title meaning "May Allah be pleased with him." It is traditionally used after the names of the male companions (Sahaba) of the Prophet Muhammad (PBUH). This phrase is rooted in the Quranic verse where Allah declares His pleasure with the early believers who sacrificed their homes and wealth for the sake of Islam. Using this title is an act of "Adab" (etiquette), acknowledging the high spiritual status and historical importance of those who supported the Prophet and preserved the faith for subsequent generations. The companions (Sahaba) hold a unique position in Islam as the generation who witnessed revelation firsthand, learned directly from the Prophet, and transmitted the religion to later generations. The Quran attests to Allah's pleasure with them: "Allah was pleased with the believers when they pledged allegiance to you under the tree" (48:18). Using Radhiallahu Anhu (or its feminine form Radhiallahu Anha, and plural Radhiallahu Anhum) is a recognition of their sacrifices and virtues. It is a Sunnah to mention the companions with honor and respect, and to ask Allah to be pleased with them. The companions are considered the best generation, and loving them is a sign of faith, while speaking ill of them is condemned. This honorific is used for all companions, including the Rightly Guided Caliphs (Abu Bakr, Umar, Uthman, Ali), the ten promised Paradise, the participants of Badr, and all those who met the Prophet as believers and died as Muslims. Using Radhiallahu Anhu connects contemporary Muslims to the noble companions, reminding them of the legacy of sacrifice, integrity, and devotion that preserved Islam and established its foundations for all time.