Invited to the English priory at Dieulwart, in Lorraine, he read a divinity lecture there, and he was next similarly employed in Marchienne College at Douai.
Venturing again into England, Barnes resided privately at Oxford in 1627 for the purpose of collecting, in the Bodleian Library, materials for some works which he intended to publish.
In consequence, however, of the efforts made by Father Clement Reyner and his interest with Albert of Austria, Barnes was carried from Paris by force, was divested of his habit, tied to a horse and hurried away into Flanders (preface to Catholico-Romanus Pacificus).
His mind giving way, he was removed to a lunatic asylum behind the church of St Paul the Less, and he appears to have been confined there until his death, which occurred in August 1661.
By the reformed party Barnes is described as the good Irenæus, a learned, peaceable, and moderate man; but catholic writers, particularly of his own order, condemn his conduct in the severest terms.