Tobia Lionelli (1647 – 17 October 1714) was a Slovene–Italian preacher and writer in the Baroque period. His sermons had a crucial role in the affirmation of Slovene as a language. He is also known by his monastic name John Baptist of Sveti Križ in Vipava (Latin: Joannes Baptista à Sancta Cruce Vippacensi; later Slovenized as Janez (Krstnik) Svetokriški, Janez Krstnik od svetega Križa, or Ivan Krstnik od Križa).