Numbers 9:16

9:16 This is the way it used to be continually: The cloud would cover it by day, ¹  and there was a fiery appearance by night.

Numbers 26:61

26:61 But Nadab and Abihu died when they offered strange fire ²  before the Lord.

[9:16]  ¹ tc The MT lacks the words “by day,” but a number of ancient versions have this reading (e.g., Greek, Syriac, Tg. Ps.-J., Latin Vulgate).

[26:61]  ² tn 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 [WBC 4], 132-33). 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 [AB], 1:598; cf. Lev 16:12 and cf. “unauthorized person” [אִישׁ זָר, ’ish zar] in Num 16:40 [17:5 HT], NASB “layman”), (2) using the wrong kind of incense (cf. the Exod 30:9 regulation against “strange incense” [קְטֹרֶת זָרָה, qÿtoret 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 [JPSTC], 59), or (4) entering the Holy of Holies at an inappropriate time (Lev 16:1-2).