I don’t know about commissioning Tetzel specifically, but the Catholic Encyclopedia is rather critical of Pope Leo X:The most important occurrence of Leo’s pontificate and that of gravest consequence to the Church was the Reformation, which began in 1517. We cannot enter into a minute account of this movement, the remote cause of which lay in the religious, political, and social conditions of Germany. It is certain, however, that the seeds of discontent amid which Luther threw his firebrand had been germinating for centuries. The immediate cause was bound up with the odious greed for money displayed by the Roman Curia, and shows how far short all efforts at reform had hitherto fallen. Albert of Brandenburg, already Archbishop of Magdeburg, received in addition the Archbishopric of Mainz and the Bishopric of Hallerstadt, but in return was obliged to collect 10,000 ducats, which he was taxed over and above the usual confirmation fees. To indemnify hiim, and to make it possible to discharge these obligations Rome permitted him to have preached in his territory the plenary indulgence promised all those who contributed to the new St. Peter’s; he was allowed to keep one half the returns, a transaction which brought dishonour on all concerned in it. Added to this, abuses occurred during the preaching of the Indulgence. The money contributions, a mere accessory, were frequently the chief object, and the “Indulgences for the Dead” became a vehicle of inadmissible teachings. That Leo X, in the most serious of all the crises which threatened the Church, should fail to prove the proper guide for her, is clear enough from what has been related above. He recognized neither the gravity of the situation nor the underlying causes of the revolt. Vigorous measures of reform might have proved an efficacious antidote, but the pope was deeply entangled in political affairs and allowed the imperial election to overshadow the revolt of Luther; moreover, he gave himself up unrestrainedly to his pleasures and failed to grasp fully the duties of his high office.newadvent.org/cathen/09162a.htm
For what it’s worth. I typically try to cross-reference what the Catholic Encyclopedia claims, but it’s a starting point.
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