Democratic MP Päivi Räsänen was questioned at Pasila police station in Helsinki on suspected incitement against sexual and gender minorities for her condemnation of The Evangelical Lutheran Church of Finland's (ELCF) involvement in a Pride event on social media in June.
Räsänen shared a photo of Romans 1:24-27 on Facebook that describes same sex relationships as "shameful" and challenged the decision by ELCF - a national Protestant denomination - to participate in Helsinki LGBT Pride.
The post read: "How can the Church's doctrinal foundation, the Bible, be compatible with the lifting up of shame and sin as a subject of pride?"
Speaking to the Christian Broadcast Network prior to the interrogation Räsänen explained why she posted the remarks online: "When praying, I got convinced that it is not my time now to jump out of the sinking boat as a parable of the Church, but to try to wake up the sleeping ones in the Church in that boat. And that's why I decided to write to social media."
The politician's conservative views on abortion, euthanasia and marriage have sparked controversy in the past when she expressed her views in a TV debate on marriage in 2010.
Tens of thousands of Christians are thought to have left the ELCF, of which Räsänen is a member, as a result of her participation in the on-screen debate.
Following Friday's police interview, Räsänen will find out if the matter will proceed to trial.
If convicted, Räsänen case would set a Finnish precedent that could impact the freedom of speech of Christians throughout the country.
Räsänen took to Facebook prior to the interrogation to thank those who have supported her throughout the investigation saying:
"Pasila police station. The interview is about to begin. Thank you for your prayer support! A peaceful mind."
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