This quote is taken from Lenoir Chambers' excellent two-volume biography of General Stonewall Jackson. It is from a Yankee officer who was a prisoner of the South during the winter of 1863, when the Army of Northern Virginia was at the peak of its accomplishments:
Their artillery horses are poor, starved frames of beasts, tied to their carriages and caissons with odds and ends of rope and strips of raw hide; their supply and ammunition trains look like a congregation of all the crippled California emigrant trains that ever escaped off the desert out of the clutches of the rampaging Comanche Indians. The men are ill-dressed, ill-equipped, and ill-provided - a set of ragamuffins that a man is ashamed to be seen among, even when he is a prisoner, and can't help it. And yet they have beaten us fairly, beaten us all to pieces, beaten us so easily that we are the objects of contempt even to their commonest private soldiers with no shirts to hang out the holes of their pantaloons, and cartridge-boxes tied around their waists with strands of rope.
As long as Generals Lee, Jackson, Longstreet and Stuart were alive and in command, the Army of Northern Virginia was one of the finest fighting units the world has ever seen.