Gregory of Tours painted a very dark picture of the conditions existing in the barbarian kingdoms of his day. The fact was that many of the bishops of the Church were worldly men who had compromised with some of the rude barbarian ideas in the hope of achieving an ultimate good. Injuriosus seems to have been in a diderent category from the rest of the bishops on this occasion. The principle on which the Church claimed exemption was put forward by him very strongly and successfully to King Lothar.
Book IV. Chapter 2:
At last King Lothar had decreed that all the churches in his kingdom should pay a third part of their income to his fisc. But when all the bishops, albeit unwillingly, had consented and signed their names, the blessed Injuriosus, manfully refusing, disdained to sign, saying: "If you wish to take God's property the Lord will quickly take away your kingdom; for it is unjust that your barns should be filled through the money of the poor who ought rather to feed at your hands." And being wroth with the king he departed unceremoniously. Then the king, much perturbed, fearing the spirit of the blessed Martin, sent after him with gifts, craving his pardon, condemning what he had done, and at the same time asking that he would ask the help of the blessed Bishop Martin on his behalf.
Source: J. P. Migne, ed., Patrologiae Cursus Completus, (Paris, 1849), Vol. LXXI, p. 269; reprinted in Roy C. Cave & Herbert H. Coulson, A Source Book for Medieval Economic History, (Milwaukee: The Bruce Publishing Co., 1936; reprint ed., New York: Biblo & Tannen, 1965), pp. 353-354.