This former Jesuit church dates from the 16th century and is the largest in Lublin; you can visit any time services are not taking place. The impressive interior is adorned with baroque trompe l'oeil frescoes by Moravian artist Józef Meyer. The treasury (skarbiec) houses precious gold and silverware, a 14th-century bronze baptismal font, and more Meyer frescoes. The vaulted roof of the so-called acoustic vestry (zakrystia akustyczna) echoes whispers from one corner across to the other.