After his return to the North, Wessel was invited to Heidelberg, to aid the Elector Palatine, Philip, in restoring the University, c. 1477.  He was without the degree in theology which would have enabled him to teach in that faculty, and was not even in orders:  indeed a proposal that he should qualify by entering the lowest grade and receiving the tonsure, he contemptuously rejected.  So the Theological Faculty would not hear him, but to the students in Arts he lectured on Greek and Hebrew and philosophy.  For some years, too, he was physician to David of Burgundy, Bishop of Utrecht, whom he cured of gout by making him take baths of warm milk.  The Bishop rewarded him by shielding him from the attacks of the Dominicans, who were incensed by his bold criticisms of Aquinas; and when age brought the desire for rest, the Bishop set him over a house of nuns at Groningen, and bought him the right to visit Mount St. Agnes whenever he liked, by paying for the board and lodging of this welcome guest.

Wessel’s last years were happily spent.  He was the acknowledged leader of his society, and he divided his time between Mount St. Agnes and the sisters at Groningen, with occasional visits to Adwert.  There he set about reviving the Abbey schools, one elementary, within its walls, the other more advanced, in a village near by; and Abbot Rees warmly supported him.  Would-be pupils besought him to teach them Greek and Hebrew.  Admiring friends came to hear him talk, and brought their sons to see this glory of their country—­Lux mundi, as he was called.  Some fragments of his conversation have been preserved, the unquestioned judgements which his hearers loyally received.  Of the Schoolmen he was contemptuous, with their honorific titles:  ’doctor angelic, doctor seraphic, doctor subtle, doctor irrefragable.’  ’Was Thomas (Aquinas) a doctor?  So am I. Thomas scarcely knew Latin, and that was his only tongue:  I have a fair knowledge of the three languages.  Thomas saw Aristotle only as a phantom:  I have read him in Greece in his own words.’  To Ostendorp, then a young man, but afterwards to become head master of Deventer school, he gave the counsel:  ’Read the ancients, sacred and profane:  modern doctors, with their robes and distinctions, will soon be drummed out of town.’  At Mount St. Agnes once he was asked why he never used rosary nor book of hours.  ‘I try’, he replied, ’to pray always.  I say the Lord’s Prayer once every day.  Said once a year in the right spirit it would have more weight than all these vain repetitions.’

He loved to read aloud to the brethren on Sunday evenings; his favourite passage being John xiii-xviii, the discourse at the Last Supper.  As he grew older, he sometimes stumbled over his words.  He was not an imposing figure, with his eyes somewhat a-squint and his slight limp; and sometimes the younger monks fell into a titter, irreverent souls, to hear him so eager in his reading and so unconscious.  It was not his eyesight that was at fault:  to the end he could read the smallest hand without any glasses, like his great namesake, John Wesley, whom a German traveller noticed on the packet-boat between Flushing and London reading the fine print of the Elzevir Virgil, with his eyes unaided, though at an advanced age.