Gustavo accepted Jesus as his Lord and Savior when he was 15 years old. He was taken in as a foster son by Doug and Shelly Kallestad in Chile.
In 1999, he traveled to Spain and Northern Africa to see firsthand the possibilities for a Chilean to minister in the Muslim world. He then received an invitation to work with a team of church planters in Melilla.
While serving in Melilla, Gustavo met and fell in love with Karissa, the daughter of a family serving on the same team. They were married in June 2006 and now have four children.
After a decade in Melilla, the Guevaras have returned to Chile, where they are serving in the South of Chile through worship ministry, church planting, and leadership development.