When Carl Crosier arrived in Hawaii in 1972, the young musician saw many local churches as "a blank slate" when it came to their music programs.

"Opportunities started opening up that I probably wouldn’t have had on the mainland," said Crosier. "I could do whatever I thought needed to be done."

Nearly 40 years later, Crosier is retiring as cantor of Lutheran Church of Honolulu, leaving behind a full slate of major contributions to the isle’s musical life. He will conduct Bach’s masterpiece, the "Mass in B Minor," this weekend as his final major concerts at the church.

"Music has been one of our core ministries for the community," said Olivia Castro, vice president of the church council. "Carl has lifted that and enhanced and grown that legacy."

Crosier, 65, never imagined that coming to Hawaii on what amounted to a whim would amount to this. "I never thought I would be conducting Bach cantatas or the big chorales. I was a keyboard person," he said.

Raised in Washington state, Crosier has innate musical talent that was apparent from a young age when he would point out deficiencies in his mother’s singing. He started piano lessons at age 5 and continued his music studies in piano performance at the University of Washington.

"I was also smart enough to get a business degree," said Crosier, who is financial adviser for St. Andrew’s Priory.

He came to Hawaii at the suggestion of a friend who was teaching music here and began attending the Lutheran church, where he met his wife, Kathy, now the organist there.

The church on Punahou Street has a long history in music, shipping in its first organ in 1906. But when Crosier arrived, it was in the midst of revitalizing its ministry, particularly the music program. Crosier was hired as the organist, and when a new organ arrived, he learned to tune it, climbing among the hundreds of pipes.

The church wanted music to be at the forefront of its community outreach efforts. "They wanted the music to be absolutely excellent at the regular worship services, but they also wanted to offer something that the community didn’t have," he said.

Crosier became music director in 1975 and has followed that mission ever since. In addition to the existing Sunday morning service choir, he established three other choral groups, including an all-men’s choir that performs Gregorian chant.

"When I started conducting, I was terrible," said Crosier, who was given the formal title of cantor in 1997. "I didn’t have the technique in terms of how to show people what you wanted. … Over the years, it was just something I learned on the job."

Despite being "really afraid" of conducting an orchestra, he also began to branch out into orchestral work, establishing the Bach Chamber Orchestra in 1981, an ensemble of about 20 musicians

Crosier’s work helped build up the church’s music library and, with composer Peter Hallock, he established a small publishing house for music, Ionian Arts, specializing in sacred choral music.

He also launched the Abendmusiken (evening concert) series, resulting in performances that have distinguished the church’s ministry, such as a 2007 performance of Bach concertos that had four harpsichords playing at once.

"It brings the church season alive for us in music," said Castro, who has sung with the church choir for 30 years. "I find it very fulfilling to be a member of the choir and to experience this great music. There’s no place like it in town."

Many of the Abendmusiken concerts have featured important works of Bach, from the Brandenburg Concertos to the major sacred chorale works. Crosier considers that a big part of his legacy.

"I have always been drawn to the music of Bach ever since I started playing the piano," he said. "When I retire I’m looking forward to having time to learning a lot of the stuff I never had time to do, for myself."