He was to fight; and that was an idea that stood him in better stead than a whole library of ethical subtilties.
Judging Tom by his own standard, he was afraid he would run--that he wouldn't "stand fire." He had not been drilled.

Heretofore, when temptation beset him, he had yielded without even a struggle, and fled from the field without firing a gun.

To go out into the great world was a trying event for the raw recruit.

He lacked, too, that prestige of success which is worth more than numbers on the field of battle.
Tom had chosen for himself, and he could not send him back.

He had taken up the line of march, let it lead him where it might.
"March on! in legions death and sin Impatient wait thy conquering hand; The foe without, the foe within-- Thy youthful arm must both withstand." Bobby had great hopes of him.