My chief concern now was how I might obtain a passport for England, through exemption from military duty. But the more certain brethren tried, though they knew how to set about the matter, and were also persons of rank, the greater difficulty there appeared to be in obtaining my object; so that in the middle of January 1829 it seemed as if I must immediately become a soldier. There was now but one more way untried, and it was at last resorted to. A believing major, who was on good terms with one of the chief generals, proposed that I should actually offer myself for entering the army, and that then I should be examined as to my bodily qualifications, in the hope, that, as I was still in a very weak state of body, I should be found unfit for military service. In that case it would belong to the chief general finally to settle the matter; who, being a godly man himself, on the major's recommendation would, no doubt, hasten the decision, on account of my desire to be a missionary to the Jews. At the same time it stood so, that, if I should be found fit for service, I should have to enter the army immediately.
Thus far the Lord had allowed things to go, to show me, it appears, that all my friends could not procure me a passport till His time was come. But now it was come. The King of kings had intended that I should go to England, because He would bless me there, and make me a blessing, though I was at that time, and am still most unworthy of it; and, therefore, though the King of Prussia had not been pleased to make an exemption in my favour, yet now all was made plain, and that at a time when hope had almost been given up, and when the last means had been resorted to. I was examined, and was declared to be unfit for military service. With a medical certificate to this effect, and a letter of recommendation from the major I went to this chief general, who received me very kindly and who himself wrote instantaneously to a second military physician, likewise to examine me at once. This was done, and it was by him confirmed that I was unfit. Now the chief general himself, as his adjutants happened to be absent, in order to hasten the matter, wrote with his own hands the papers which were needed, and I got a complete dismissal, and that for life, from all military engagements. This was much more than I could have expected. This military gentleman spoke to me in a very kind way, and pointed out certain parts of the Scriptures, which he in particular advised me to bring before the Jews, especially Romans xi.
On considering why the Lord delayed my obtaining this permission, I find that one of the reasons may have been, that I might both be profited myself by my stay in Berlin, and that I also might be instrumental in benefiting others. As to the first, I would mention, that I learned a lesson in Berlin which I did not know before. Whilst I was at Halle, I thought I should much enjoy being among so many christians as there are in Berlin. But when I was there I found, that enjoyment in the Lord does not depend upon the multitude of believers, by whom we are surrounded. As to the second point, perhaps the last day may show, that the Lord had some work for me in Berlin: for, from the time of my coming until I left, I preached three, four, or five times every week in the wards of a poorhouse, which was inhabited by about three hundred aged and infirm people. I also preached once in a church, and likewise visited one of the prisons several times on Lord's days to converse with the prisoners about their souls, where I was locked in by the keeper with the criminals in their cells.
On the whole my time in Berlin was not lost; and I was in a better state of heart than I had been for any length of time before, I was not once overcome by my former outward besetting sins, though I have nothing to boast of even as it regards that period; and were only the sins of those days brought against me, had I not the blood of Jesus to plead, I should be most miserable. But I think it right to mention, for the glory of God, as I have so freely spoken about my falls, that whilst I was more than ever unobserved by others; and whilst I was living in the midst of more gaiety and temptations than ever; and had far more money than at any previous time of my life; I was kept from things of which I had been habitually guilty in my unconverted days!--My health was in a very weak state, almost the whole time whilst I was staying in Berlin, and was in no degree better, till, on the advice of, a believing medical professor, I gave up all medicine.