The expression is often used when expressing pity towards a person, or when seeking pity.
A police officer arrives on the scene.
Police Officer: "What you are doing is illegal, give me all your stuff and get the fuck out of here"
Unemployed man: "I know officer and I'm sorry, I can't get a job and I haven't eaten since yesterday afternoon. You're not going to take a sod's honest dinner are you?"
Police Officer: "No, this time I'll let you off with a warning. Now get out of here."