The Unintentional Sin Conversation

In verse 32, a man picks up sticks on the Sabbath in order to start a fire. The people ultimately based on the word of the Lord stone him and kill him for his high handed sin. This is kind of like an open public act of rebellion against the Lord. And so he's just putting up his hand and saying, I'm going to live my own way. It might sound like she's just picking up sticks. What's the big deal? But why is he picking up sticks to build a fire? What happens when he builds a fire? Right?