Life and teachings
Gish condemned the teachings of Tevahr and the Great King for their emphasis on "taygahn" (intellectual love and understanding) as the proper means of gaining Yahvo's salvation and entering the Perfect Age. He taught that obedience to Yahvo's commands was the key, and that taygahn was just an excuse to do as one pleased.
In his book Yahvo Alone, Gish proclaimed that one of Yahvo's commands was to have no interaction with outside (non-D'ni) peoples and cultures. This was well received by the public, as popular sentiment had been moving towards isolationism since the days of Kings Lemashal and Ishek.
King Adesh was a religious man, but an intolerant one, and had Gish arrested many times. Ultimately, Gish was assassinated by the Relyimah — the D'ni secret intelligence agency — by order of Adesh, possibly at the urging of his prophetess, Trisari. This act provoked great public outrage, and led to the assassination of Adesh in 5701, possibly by a close advisor. As a further consequence, it also led to the disbanding of the Relyimah by Adesh's successor, King Lanaren.
Political and religious influence
Gish became a martyr, and his adherents – the Followers of Yahvo – increased in number through the reigns of Kings Lanaren, Asemlef, and Jaron. Most of the old cults (such as The Cult of the Tree and The Cult of the Sacred Stone) disappeared during this time, and the remaining factions were focused on Yahvo in one way or another, many based on the teachings of Gish.
In 6656 DE, King Rikooth married Hisha, a strong believer in Gish and the fallacy of the Great King. Rikooth tired of her views in 6700 DE, and banished her from the Palace, along with his youngest son, Kerath, who had been raised in Hisha's beliefs. Kerath's belief in the teachings of Gish strongly contributed to his conviction that the D'ni form of government needed to change.
By the end of the Mee-Dis War (circa 7000 DE) nearly all D'ni were followers of Gish and his isolationist teachings.