Former Engadine Anglican Church youth leader Karen Darda - a missionary in Japan for 26 years - farewelled after death at 58

A similar number of mourners watched online as there was no more room in the church.

Archbishop of Sydney Kanishka Raffel led the service on Wednesday.

Ms Darda passed away on July 7 at the age of 58 in Royal Prince Alfred Hospital.

The missionary took ill on a flight between Dubai and Japan and was admitted to a Singapore hospital's intensive care unit.

After surgery and a period of stabilisation, she was medevacked to Sydney, but doctors were unable to save her life.

Senior Minister of the Engadine-Heathcote Anglican Church, Rev James Warren, said the number of people present "speaks volumes for how Karen was regarded, not only in the shire, but across the world".

"Karen attended Engadine High as a student and was a regular congregation member at our church, where she became a youth leader," he said.

"After she completed the HSC, she completed her teacher training and then went to Japan to teach English.

"On her return to Australia, she worked part-time to support herself while she attended Moore Theological College at Newtown.

"Karen had strong Christian convictions and was determined to use her skills to tell the people of Japan about the saving grace of Jesus Christ.

"She was an incredible ambassador for Him and an amazing evangelist. Only 1.5 per cent of Japan is Christian. She even helped establish a church in Urayasu-shi, not far from Tokyo.

"In total Karen was in Japan, speaking fluent Japanese, for more than a quarter of a century, from 1991 to 2017."

Rev Warren said Ms Darda helped deliver food and clothing during the 2011 Great East Japan Earthquake, which led to a tsunami in which 20,000 people died and 500,000 people were forced to evacuate their homes.

"We all know Karen had a deep love and passion for sharing the gospel with Japanese people. She served with KGK (university ministry), supporting and equipping students in discipleship and evangelism for many years," he said.

"Later, under the Christian Missionary Society she also joyfully poured herself into the ministries of the churches she was a part of, getting involved in a broad range of ministries.

"Karen always sought opportunities to connect deeply with people, share from the Bible and point them to Jesus, whether through Mums and Bubs groups and playgroups, Bible studies, meals with high schoolers, holiday and after school clubs, exercise classes, camps, and many other outreach events."

Rev Warren said, in 2018, Ms Darda relocated to Dubai where, in a large international church, she used her fluent Japanese and knowledge of the culture to shine the light of Christ to the many Japanese who had come to that city for work.

"She also taught Japanese women the English language," he said. "This was to be her last posting before she died."

Ms Darda family requested, In lieu of flowers, donations be made to the Christian Missionary Society.