Machen had a long struggle before committing to the Christian ministry. He did graduate study with the foremost exponents of liberal theology in Germany in 1905 and 1906; confusion and doubt were the result. He returned to teach at Princeton only because he was not required to seek ordination immediately. It took seven or eight years for him to decide that he was called and qualified for ordained ministry. His 1914 ordination sermon contains a few lines that suggest he would oppose both the building-fixated and "Reconquista" of the mainline and vapid, modern megachurch evangelicalism. Quoting Stonehouse's biography:—
“How is religion to be made a joyful thing?”
The answer he averred is not to be found merely by cheering up religion. “Noble churches, good music, brilliant preaching—these things in things, in themselves, are none the less worldly because enjoyed within in consecrated walls. Sometimes they are not religion, but a diversion from religion.”
And speaking of buildings, Machen was a great lover of the art and Gothic architecture of the mostly Romanist churches of Europe. He seemed to have little concern about what we’d consider Second Commandment violations. This is not surprising considering the Victorian sensibilities of the mainline church of the time and his own family. He was, however, intensely concerned with the Christian Sabbath, often commending its blessings and lamenting when his observing it was hindered by circumstances or by being in places (like Germany or big cities) where the Lord’s Day was held in low esteem. More than once he lost days of mountain climbing in the Alps because of his Lord’s Day convictions.
Machen’s service in World War I was with the YMCA. He desired to do “religious work” (preaching and teaching) in Europe, but the 9 months he served before the November 11, 1918 armistice was spent primarily in YMCA canteens more or less near the front in Belgium and France. The ill-prepared armies relied on the YMCA as a critical support for the morale and personal needs of soldiers. Machen served French and American units. His main jobs were making and selling hot chocolate, vending cigarettes, providing recreational activities, and sending money orders home for troops. He often slept and operated in partially bombed-out houses (or the cellars thereof). Rat killing was a necessary skill. At least once he had to bug out when a German advance overran positions near him. And he narrowly escaped injury or death from near artillery misses several times. Near the end of the fighting he found himself serving troops in the trenches at the very front or ministering to the wounded and dying at the dressing stations, even bearing stretchers under fire.
Again, quoting from a letter in the Stonehouse biography, we find Machen downplaying his bravery and humorously mentioning certain practical matters.
Good-bye to all my things.1 The (Germans) have swept over my post [at St Mard], One of the foyer (canteen) directors of the region is rumoured to be taken prisoner; others had a very much harder time escaping than I had. My former post was the of hard fighting.
I have been directed to wait here in Paris till tomorrow when instructions may be given me. Naturally clothes are almost my first concern. The prices are something terrific—I paid 185 francs for a pair of high boots. But I should not mind if I could only get the things that I desire. French underwear is cut in the queerest way imaginable2 and the American variety cannot be found.
Machen was no radical anti-papist. He often found the services of the many Romanist military chaplains more edifying than the liberal protestant variety. He eschewed chaplain service3 because chaplains were officers and he desired to be with the common soldier with no barriers between. He considered service in the ambulance corps but rejected that course because of his understanding that volunteers for that service were sometimes diverted to transporting ammunition. Yet, he found himself working closely with the ambulance corps and medical units. And he sometimes found himself working with nuns:
The dressing station was in a large house occupied by some sisters of charity. Now I am a Protestant of the most uncompromising sort, and I do not believe a bit in nunnery; but I want to testify that those ladies were admirable. You should have seen the way they cared for the American wounded and doctors and ambulance men, as well as for the crowd of children that had fallen to their care.
If Machen’s WW1 service interests you the excellent volume of his wartime letters compiled by Barry Waugh is available (as of March 2024) for the hugely discounted price of $5.
Machen had to leave all of his personal effects and all of his hot chocolate-making utensils and supplies behind in the retreat. He lamented that the Germans might be enjoying the YMCA’s chocolate
Who among us is surprised by this fact?
He did not consider serving as a soldier, being in his late 30s by 1918. As a Germanophile (and very much NOT an Anglophile), he was quite skeptical about the war early on but came around to affirming its necessity by its end.