The Leadership of Berean Bible Church

Berean Bible Church has both elders and deacons. The elders have spiritual and administrative authority over the church, while the deacons assist the elders by overseeing physical areas.

Kahu Daniel Costales (Teaching Elder)

Daniel Costales was born on the island of Kauai, Hawaii, to Alice and "Pastor Timmy" Costales. His early years were spent at Anahola Baptist Church and Kauai Christian Academy on the island of Kauai. During his teen years, Daniel's parents served for five years at Koolau Baptist Church and Academy on the island of Oahu. God granted Daniel salvation at an early age and burdened him in his youth for pastoral ministry. In 1999, he earned his Master of Divinity degree from The Master's Seminary in Sun Valley, California. Four months after graduation, he was installed as the Kahu (Hawaiian for Pastor or Shepherd) of Berean Bible Church in Hilo, Hawaii.

Kahu Daniel is passionate about theology and teaching God's truth to God's people. It is his privilege to lift up the name of Jesus through the careful exposition of the Scripture at every church worship service. The church supports Kahu Daniel full time which gives him the freedom to meet for one-on-one and family counseling. Write to him at to set up a private counseling session. Kahu's hobbies include playing soccer, hanging out with his family, reading Christian biographies and listening to Bible expositors on his iPod. You might catch him at odd hours picking out tunes on his guitar and serenading anyone who will listen. Add him on Facebook to keep up with his family antics.

Kahu's wife Karen is an important part of the ministry. Born in Mexico and reared in a missionary home, she was drawn to the Savior at an early age. Her desire to serve the Lord in ministry has been fulfilled at her husband's side here at Berean Bible Church. After college Karen worked as an elementary school teacher and high school Spanish teacher. In more recent years, she has dedicated her time to being a keeper at home and teaching at a local public charter school. At home between laundry loads and dinner dishes, you might find her planning Mexican food events and checking her Facebook messages. Kahu and Karen have been married since 1995 and have four children - Hoku, Timothy, Liana Joy and Kekoa.


Aaron Tresham (Elder)

Aaron Tresham was born in McMinnville, Oregon. He was raised in a Christian home and placed his faith in the Lord as a child. Aaron earned a B.A. from Lewis and Clark College and an M.S. in Mathematics from the University of Oregon. At UO he met Jennifer, who was born and raised on the Big Island, and they were married in 2004. Following graduate school, Aaron attended The Master's Seminary, while Jen taught high school math. Aaron eventually earned an M.Div., Th.M., and Th.D. in New Testament. After teaching math at Northern Arizona University for two years, the Lord opened up an opportunity to teach near Jen's family. So in 2013, Aaron and his family moved to Hawaii, where he currently teaches math at the University of Hawaii at Hilo. Jen keeps busy homeschooling their two sons, Nathaniel and Matthew. 


Mark Morikawa (Elder)

Mark Morikawa was born in Honolulu, Hawaii. He heard the gospel throughout his childhood and put his faith in Christ as a teenager. Mark earned a B.A. in Communication from the University of Hawaii at Manoa in 2007 and a M.A. in Exegesis and Theology from Bethlehem College and Seminary in 2023. He then worked about four years as an adolescent substance abuse counselor on Oahu. In 2012, Mark started attending Berean Bible Church, while working for Goodwill's youth program in Hilo. He currently works as a Supervisor for the Department of Human Services. Mark's wife, Lima, was born in California and grew up primarily on Oahu. She became a Christian in 2011. Lima graduated from the University of Hawaii at Hilo in 2015 and married Mark that same year. Mark and Lima have two sons, Ezra and Isaac.


Andrew Repp (Elder)

Andrew Repp was born in Plymouth, Indiana, but grew up in St. Louis, Missouri, and Greenville, South Carolina. He was raised in a Christian home and put his faith in Christ when he was a child. Andrew obtained his undergraduate degree in mathematics from Bob Jones University and a Ph.D. in mathematics from Virginia Tech. Burdened to serve in Christian education, he moved to Hawaii in 1998 to teach high school math and science at Christian Liberty Academy in Hilo. In 2013 he took a leave of absence from this position to earn a Ph.D. in astronomy from the University of Hawaii at Manoa, returning to Christian Liberty in 2020.



Landon Collins (Deacon)

Landon Collins was born in North Platte, NE. He grew up in a Christian home and placed his faith in Christ during college. He attended the University of Nebraska - Lincoln where he earned a B.S. in Biology and Biochemistry. He met his wife Jenn at UNL, and they were married in 2008. They first visited Hawaii on their honeymoon on Kauai. After moving to Texas, Landon attended Parker University earning Doctor of Chiropractic and APRN degrees in 2012. Landon and Jenn moved to Hilo in 2014 for a job opportunity, and the couple started attending Berean Bible Church. They lived on the Big Island for 2 years before moving to Kansas in 2016, but God had plans for them to move back to Hilo in 2018 when Landon was offered a job at Hilo Medical Center. He is currently working at a hospital-owned Urgent Care clinic in Keaau. Landon and Jenn have 3 children, Addison, Jameson, and Cameron, and 2 dogs, Kea and Loa. Landon's wife Jenn graduated from the University of Nebraska with a B.A. in Music Education. She enjoys homeschooling their children and teaching music in the children's ministry at BBC.

Landon oversees the tech team, dealing with all things audio/visual.


Dmitriy Sumtsov (Deacon)

Dmitriy Sumtsov was born in Groznyy, Russia. He grew up in a large Christian family of ten and immigrated to the U.S. in 1997. The Lord saved him at the age of 17. He got involved in youth ministry, and later as a missionary he visited Russia, where he met his future wife Elena. After getting married, they moved to Washington state. Elena became a certified public school teacher and taught high school German. In 2009 Dmitriy received his certification in Landscape Design from Ashworth College. In 2017 he earned an Associate of Science in Mechanical Engineering from Clark College in Vancouver, WA. He was involved in children's ministry for about ten years and helped to maintain the church property. In 2020 the family moved to Hawaii. Dmitriy continues to work on various landscaping projects in the area. Dmitriy and Elena have five daughters, Tina, Alexandra, Elizabeth, Ivanka, and Mary and one son, Kekoa. They enjoy working on their homestead, growing plants, and keeping bees and chickens.

Dmitriy oversees the church grounds.