The earlier acquaintance between the Reformer and the great Humanist, Erasmus, had now developed into an irreconcilable enmity. The latter had long been unable to refrain from venting, in private and public utterances, his dissatisfaction and bitterness at the storm aroused by Luther, which was distracting the Church and disturbing quiet study. Patrons of his in high places--above all, King Henry VIII. of England--urged him to take up the cause of the Church against Luther in a pamphlet; and, difficult as he felt it to take a prominent part in such a contest, he was the less able to decline their overtures, since other Churchmen were reproaching him with having furthered by his earlier writings the pernicious movement. He chose a subject which would enable him, at any rate, while attacking Luther, to represent his own personal convictions, and to reckon on the concurrence not only of Romish zealots but also of a number of his Humanist friends, and even many men of deeply moral and religious disposition. Luther, it will be remembered, had told him plainly from the first that he knew too little of the grace of God, which alone could give salvation to sinners, and strength and ability to the good. Erasmus now retorted by his diatribe 'On Free Will,' by virtue whereof, he said, man was able and was bound to procure his own blessing and final happiness. Luther, on perusing this treatise, in September 1524, was struck with the feebleness of its contents. So far, indeed, from defining the operation of the human will, Erasmus floated vaguely about in loose and incoherent propositions, evidently not from want of extreme care and circumspection, but from the fact that, in this province of antiquarian research, he failed in the necessary acuteness and depth of observation and thought. He declared himself ready to yield obedience to all decisions of the Church, but without expressing any opinion as to the real infallibility of an ecclesiastical tribunal. Throughout his whole treatise, however, there were personal thrusts at his enemy.