The Holy Trinity Lutheran Church follows the teachings of the Evangelical Lutheran Church. Evangelical Lutherans believe in the Triune Godhead, open sacrament and support women in the clergy. The church is one of two Lutheran churches on the island, but the two maintain small differences in doctrine.
The church was founded at the Keewaydin Clubhouse in 1948 and soon built a small brick chapel on S.E. 40th Street. Today, the chapel remains but is dwarfed by a large, brightly-lit sanctuary with room to seat more than 400 parishioners.