Not like the men of the crowd
Who all round me to-day
Bluster or cringe, and make life
Hideous, and arid, and vile;
But souls tempered with fire,
Fervent, heroic, and good,
Helpers and friends of mankind.

But Arnold also recognised, in his far better known "Dover Beach", that the certitudes of his father were in retreat: 

The Sea of Faith
Was once, too, at the full, and round earth's shore
Lay like the folds of a bright girdle furled.
But now I only hear
Its melancholy, long, withdrawing roar, 
Retreating, to the breath 
Of the night-wind, down the vast edges drear
And naked shingles of the world.

In 1918, Dr Arnold was one of the Eminent Victorians mocked by Lytton Strachey, in his book of that name. Bloomsbury found such earnestness ridiculous, but they were not the only writers who noticed that things had changed. In Evelyn Waugh's Decline and Fall, which appeared in 1928, the public schools are represented by the rackety Captain Grimes, a man of whom Dr Arnold would not approve, while Paul Pennyfeather, a dim undergraduate to whom things happen, has to return Dean Stanley's Eastern Church to the college chaplain after being sent down from Oxford. Pennyfeather gets the book back when he returns to the university and resumes his life of obscurity.

For Waugh, Christianity could no longer be the great animating principle that it was for Dr Arnold. I do not want to exaggerate this change. Much of the life of the Church of England, and of the other churches, flows underground, or at least quite unnoticed. To some people and some schools, perhaps more than we realise, Christianity remains of defining importance. But as a rallying cry, it will not do. Secular intellectuals inform us that even to use the expression "Christian name" is offensive to members of other faiths.