Jesus pulls no punches as he speaks of the wickedness of the human heart and its evil thoughts. His list of examples started with sexual immorality. Next he speaks of theft and murder. The temptation to satisfy ourselves and not think of others runs deep. That leads to us grabbing what we want and not considering others; maybe even taking what should be theirs. Such self-centredness also sits behind the hatred and pride from which murder can spring. So that even when the crimes of theft and murder are never committed, their seeds are found in all our hearts. Changes our circumstances and we can be capable of terrible things. But if we will recognise this sad truth, then there is hope for Jesus can save us from our sin.
And here is a short talk based on the same passage: He Changed The World (Episode 26)