Character mistake: While General Patton is in Malta as a decoy for a fake Greek invasion, he gives some aides a tour of the fortifications there and tells them that they were "defended by 400 Knights of Malta and 800 mercenaries against a force of 40,000 Turks." He is referring to the Siege of Malta in 1565, but the date he gives is 1528.
Character mistake: In Bradley's first briefing with Patton in Tunisia, he mentions the German tanks were diesel as opposed to American tanks using gasoline and more prone to burn if hit. Actually, all German tank engines used low grade gasoline. Only a few captured Russian T-34 used diesel and none of those reached North Africa.
Answer: "The front" means the front line, i.e., where the enemy is being engaged. He's saying that since the soldier isn't physically injured, he should be fighting, not (as Patton sees it) being a coward and shirking his duty.