During this period the Cologne church controversy was escalating, in which he was involved through his own writings, and in which he took the side of the founder of the Aachener Priesterkreis and ultramontanist, Leonhard Aloys Joseph Nellessen, arguing against the tenets of Hermesianism.
Im zu jener Zeit eskalierenden Kölner Kirchenstreit, in dem er durch eigene Schriften involviert war, stand Laurent auf Seiten des Gründers des Aachener Priesterkreises und Ultramontanisten, dem Oberpfarrer Leonhard Aloys Joseph Nellessen und argumentierte mit gegen die Thesen des Hermesianismus.