Deckers, Jan a Flemish theologian, was born at Hazebrouck about 1559. He studied at Douay, became a Jesuit. at Naples, taught, at Douay and Louvain, philosophy and theology, and became chancellor of the university at Gratz and rector of the college at Olmitz, in Moravia. He died at Gratz in 1619. His principal works are, Tabula Chronographica (1605): — Theologicae Dissertationes, etc. (Paris, 1699): — Tabula Expansa Ephemeridum. See Hoefer, Nouv. Biog. Generale, s.v.