“Now Nadab and Abihu, the sons of Aaron, each took his censer and put fire in it and laid incense on it and offered unauthorized fire before the LORD …” (v1). When Aaron’s priestly sons decided to offer “strange” incense before God, using their own ideas about worship rather than His instructions, God’s “fire” blazed out, and they died. God’s holy presence, like the power of the Sun, was life-giving when approached correctly but dangerous when misjudged or treated lightly.
“You are to distinguish between the holy and the common …” (v10). Our made-up ideas about the supernatural are small compared to reality. God’s holiness is far more powerful, far brighter and more beautiful than we can imagine.