Say, Lad, Have You Things to Do?

Say, lad, have you things to do? Quick then, while your day's at prime. Quick, and if 'tis work for two, Here am I man: now's your time. Send me now, and I shall go; Call me, I shall hear you call; Use me ere they lay me low Where a man's no use at all; Ere the wholesome flesh decay And the willing nerve be numb, And the lips lack breath to say, "No, my lad, I cannot come."