Not the smartest Jedi on the block
You don’t need to know much about Star Wars to understand that Luke Skywalker is a complete moron in this scene. Just so we’re on the same page, a lightsaber is the deadliest weapon in the entire galaxy and should be handled with great care. Here, we see Luke pointing the lightsaber directly at his face.
To be fair, Luke is hardly a Jedi Knight in this scene. He’s just some young, clueless Padawan who would probably kill himself if Obi-Wan wasn’t around. Also, this isn’t a still-frame from Episode IV. This is just a behind-the-scenes picture of Mark examining the lightsaber prop.