38 The expression אֵשׁ זָרָה (’esh zarah, “strange fire”) seems imprecise and has been interpreted numerous ways (see the helpful summary in J. E. Hartley, Leviticus [ 4], ). The infraction may have involved any of the following or a combination thereof: (1) using coals from some place other than the burnt offering altar (i.e., “unauthorized coals” according to J. Milgrom, Leviticus [], 1:; cf. Lev 16:12 and cf. “unauthorized person” [אִישׁ זָר, ’ish zar] in Num 16:40 [17:5 ], “layman”), (2) using the wrong kind of incense (cf. the Exod 30:9 regulation against “strange incense” [קְטֹרֶת זָרָה, qétoret zarah] on the incense altar and the possible connection to Exod 30:34–38), (3) performing an incense offering at an unprescribed time (B. A. Levine, Leviticus [], ), or (4) entering the Holy of Holies at an inappropriate time (Lev 16:1–2). This event is narrated in Lev 10:1–7.

In other versions

But Nadab and Abihu died when they offered unauthorized fire before the Lord.

But Nadab and Abihu died when they made an offering before the Lord with unauthorized fire.)

but Nadab and Abihu died when they presented unauthorized fire before the Lord.

But Nadab and Abihu died when they burned before the Lord the wrong kind of fire, different than he had commanded.

But Nadab and Abihu died when they presented strange fire before Yahweh.

And Nadab and Abihu died, when they offered strange fire before the Lord.

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