He became involved in a controversy with Joseph Justus Scaliger, formerly his intimate friend, and others, wrote Ecclesiasticus auctoritati Jacobi regis oppositus (1611), an attack upon James I.
His first step was to recover control of the mint, and place it in the hands of capable middle-class merchants and bankers, like Caspar Beer, Jan Thurzo, Jan Boner, the Betmans, exiles for conscience' sake from Alsace, who had sought refuge in Poland under Casimir IV., Justus Decyusz, subsequently the king's secretary and historian, and their fellows, all practical economists of high integrity who reformed the currency and opened out new ways for trade and commerce.
Had been the pupil of Matthew of Pisa and summoned Justus Balduinus to his court to write the national history in Latin, while later King John II.
In 1840 the appearance of Chemistry in its Application to Agriculture and Physiology by Justus von Liebig set on foot a movement in favour of scientific husbandry, the most notable outcome of which was the establishment by Sir John Bennet Lawes in 1843 of the experimental station of Rothamsted.
In 1520 he had brought out a primer of religion dealing briefly with the Decalogue, the Creed and the Lord's Prayer; and Justus Jonas, Johannes Agricola and other leaders had done something of the same kind.
See Briefswechsel des Justus Jonas, gesammelt and bearbeitet von G.
Shenstone, Justus von Liebig, his Life and Work (1895).
The work of Justus Byrgius is described in the article Logarithm.
It was made a condition that Christianity should be tolerated in Northumbria, and accordingly Paulinus was consecrated bishop by Justus in 625, and was sent to Northumbria with iEthelberg.
His translation of the German Catechism of Justus Jonas, known as Cranmer's Catechism, appeared in the following year.