Jacqueline Furnari said her father, Andrew Brunson from North Carolina, lost at least 50lb while in jail but he feels "blessed" to suffer for his Christian faith.
She was quoted by the Christian Post as saying: "[He] has been permanently changed by this experience.
"Even when this ordeal is over, he will never be the same person that he was."
On Wednesday, a court decided Brunson, who leads Izmir Resurrection Church, could leave his cell and be placed under house arrest.
Mrs Furnari told guests at a US State Department event raising awareness of religious persecution that missing out on time with family was the hardest part of her father's experience in jail.
Appearing at the inaugural State Department Ministerial to Advance Religious Freedom, she also criticised the "ridiculous testimony" of prosecution witnesses called to give evidence in the trial.
.@POTUS & I made clear last week and have worked tirelessly for months to free Pastor Andrew Brunson. He should have been freed long ago. He's now under house arrest—but we won't stop until he's fully released and reunited with his family, friends, and church. #FreeAndrewBrunson https://t.co/E1MmMlD3ed
— Vice President Mike Pence (@VP) July 25, 2018
She went on to say: "In his trial last week, my father forgave the witnesses who falsely testified against him, saying, 'My faith teaches me to forgive, so I forgive those who testified against me.'
"He went on to say, 'It is a privilege to suffer for the sake of Christ.'"
We welcome long overdue news that Pastor Brunson has been moved from prison to house arrest in #Turkey, but it is not enough. We have seen no credible evidence against Mr. Brunson, and call on Turkish authorities to resolve his case immediately in a transparent and fair manner. pic.twitter.com/So2A4hfinZ
— Secretary Pompeo (@SecPompeo) July 25, 2018
Mr Brunson was arrested on 7th October 2016 and charged with links to groups the Turkish government blames for staging a coup bid in July 2016.
Supporters claim he is innocent and being used as a political pawn by Turkey as it tries to secure the extradition of controversial cleric Fethullah Gulen from the US.
Explaining how her father had missed his daughter's wedding and graduation, Mrs Furnari added: "These are the things that pain my dad the most - not being able to be with us and missing out on life with his family."
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