Ovid tells Atticus that like the soldier, the lover ought to be on his guard and that Love is a species of warfare.
Every lover is a soldier, and Cupid has a camp of his own; believe me, Atticus, every lover is a soldier. The age which is fitted for war, is suited to love as well. For an old man to be a soldier, is shocking; amorousness in an old man is shocking. The years which generals require in the valiant soldier, the same does the charming fair require in her husband. Both soldier and lover pass sleepless nights; both rest upon the ground. The one watches at the door of his mistress; but the other at that of his general. Long marches are the duty of the soldier; send the fair far away, and the lover will boldly follow her, without a limit to his endurance. Over opposing mountains will he go, and rivers swollen with rains; the accumulating snows will he pace.
About to plough the waves, he will not reproach the stormy East winds; nor will he watch for Constellations favourable for scudding over the waves. Who, except either the soldier or the lover, will submit to both the chill of the night, and the snows mingled with the heavy showers? The one is sent as a spy against the hostile foe; the other keeps his eye on his rival, as though upon an enemy. The one lays siege to stubborn cities, the other to the threshold of his obdurate mistress: the one bursts open gates, and the other, doors. Full oft has it answered to attack the enemy when buried in sleep; and to slaughter an unarmed multitude with armed hand. Thus did the fierce troops of the Thracian Rhesus fall; and you, captured steeds, forsook your lord. Full oft do lovers take advantage of the sleep of husbands, and brandish their arms against the slumbering foe. To escape the troops of the sentinels, and the bands of the patrol, is the part both of the soldier, and of the lover always in misery. Mars is wayward, and Venus is uncertain; both the conquered rise again, and those fall whom you would say could never possibly be prostrate.
Whoever, then, has pronounced Love mere slothfulness, let him cease to love: to the discerning mind does Love belong. The mighty Achilles is inflamed by the captive Briseis. Trojans, while you may, destroy the Argive resources. Hector used to go to battle fresh from the embraces of Andromache; and it was his wife who placed his helmet on his head. The son of Atreus, the first of all the chiefs, on beholding the daughter of Priam, is said to have been smitten with the dishevelled locks of the raving prophetess. Mars, too, when caught, was sensible of the chains wrought at the forge; there was no story better known than his, in all the heavens.
I myself was of slothful habit, and born for a lazy inactivity; the couch and the shade had enervated my mind. Attentions to the charming fair gave a fillip to me, in my indolence; and Love commanded me to serve in his camp. Hence it is that thou seest me active, and waging the warfare by night. Let him who wishes not to become slothful, fall in love.
End of Elegy IX by Ovid