These communications seriously affected Luther: the elector attacked him on his weakest side. The reformer venerated Melancthon, but he knew to what sacrifices his desire for union had more than once been on the point of leading him. If Melancthon was the champion of unity, Luther was the champion of truth: to guard the whole truth with a holy jealousy was his principle. The Reformation, he thought, must triumph by fidelity to the Word of God, and not by the negotiations of kings. Recovering from his first impressions, he said to Melancthon: ‘I begin to suspect these ambassadors.’[747] From that moment he never uttered a word in favor of the journey. Still the dangers of the protestants of France were never out of his thoughts. ‘Must we abandon our brethren?’ he asked himself perpetually. A luminous idea occurred to him: Suppose the evangelicals were to leave France, and come to Germany in search of liberty.[748] He engaged to receive them well. Luther anticipated _the Refuge_ by a century and a half. [Sidenote: Harsh Letter To Melancthon.] By degrees the elector gained ground, and the extraordinary adventure proposed to Melancthon became more doubtful every day. From the first the prince had had the politicians and courtiers with him; then the men of letters and citizens, alarmed by the sinister reports, had gone over to his side; and now Luther himself was convinced. Melancthon remained almost alone. His sympathetic heart longed to remove the sword hanging over the heads of the French evangelicals, and it seemed as if nothing could stop him. John Frederick endeavored to convince him. Beyond a doubt, the French reformation, driven at this moment by contrary winds, must reach the haven; but the task must be left to its own crew. Every ship must have its own pilot. John Frederick, therefore, wrote a severe letter to Melancthon, and the tender-hearted divine had to drink the cup to the dregs. ‘You declared that you were ready to undertake a journey to France,’ said the elector, ‘without consulting us. You should, however, have thought of your duty to us, whom God has established as your superior. We were greatly displeased to see that you had gone so far in the matter. You know the relations existing between the King of France and the emperor, and you are not ignorant that we are obliged to respect them. We desire that foreign nations should be brought to the Gospel; but must we go to them to effect their conversion?[749] The undertaking is of great extent, and the success very doubtful. The letters we receive from France are well calculated to make us despair of seeing the evangelical seed bear fruit there. _Do you desire to disturb the public peace of the German nation, and while we have a right to expect that you will second us, do you presume on the contrary to vex us and thwart our plans?_’