TSK · Exodus 8:27

They will listen to your voice, and you shall come, you and the elders of Israel, to the king of Egypt, and you shall tell him, 'Yahweh, the God of the Hebrews, has met with us. Now please let us go three days' journey into the wilderness, that we may sacrifice to Yahweh, our God.'

Our livestock also shall go with us. Not a hoof shall be left behind, for of it we must take to serve Yahweh our God; and we don't know with what we must serve Yahweh, until we come there."

Nadab and Abihu, the sons of Aaron, each took his censer, and put fire in it, and laid incense on it, and offered strange fire before Yahweh, which he had not commanded them.