'Strange' in the Bible

But Nadab and Abihu died in the presence of the Lord when they offered strange (unholy, unacceptable, inappropriate) fire before the Lord in the Wilderness of Sinai; and they had no sons. So Eleazar and Ithamar served as priests in the presence and under the supervision of Aaron their father.

But Nadab and Abihu died [in the presence of God] when they offered [in their ceremonial censers] strange [unholy, unacceptable, unauthorized] fire before the Lord.