This officer is an old friend of Sharpe's. When Lawford was a new lieutenant in the army, Sharpe was a sergeant, and he taught Lawford many of the things that later enabled him to succeed and become a fine soldier and officer. Lawford repaid the favor by teaching Sharpe how to read and write while the two were imprisoned in India. Sharpe's literacy made him eligible for commission. So it can be said that Lawford and Sharpe owe each other for their success.