Parshat Vayishlach tells of Jacob wrestling with an angel, and Jacob asks the angel an unusual question: "What's your name?"

The great commentator Sforno, who lived in 16th century Italy, explains that this angel represented the Yetzer Hara, the tendency toward undisciplined behavior.

The Yetzer Hara always challenges a person in the area that he needs improvement. So by asking the angel's name, Jacob is in effect asking - "In what area are you challenging me?" Jacob wanted to know in what area he needs to improve.

The angel gives Jacob the following answer: "Don't ask my name."

This answer gives us insight into the ways of the Yetzer Hara - always trying to keep us from seeking out the truth!

On another level, the Yetzer Hara was saying: "I have no name – I'm nothing." In other words, a person's drive for undisciplined behavior is really an illusion.

This teaches us an important lesson for our own lives. When we're struggling to do the right thing - e.g., not cheating, not being critical of others – and we hear that little voice arguing inside our head, that's when we can remind ourselves that the Yetzer Hara "has no name" - it's just a bluff and we can just go right ahead and ignore it.

The story is told of the saintly Chafetz Chaim starting to get out of bed on a cold morning in Poland, when the Yetzer Hara began arguing with him, saying, "Stay in bed - you're an old man!" At which point the Chafetz Chaim jumped out of bed and retorted, "That may be true, but you're even older!"