Exodus 30

1 Incense gives off a sweet smelling smoke when burned. Incense could be used as atonement (Num 16:47), but also was symbolic of prayer (Rev 8:3). The thick smoke of the incense could effectively hide the mercy seat when the priest would approach it (Lev 16:13).
7 The morning and evening duties included a burnt offering, tending the lamp stand, and burning incense.
9 God was going to give a special recipe for the incense, and the punishment for burning unauthorized incense was death (Lev 10:1-2). Also, nothing beside incense was to be burned on this altar. Grain (and meat) offerings were to be burned on the bronze altar outside the tabernacle. Only there could incense be mixed with other offerings.
10 Once a year the tabernacle was to be purified (Lev 16:18-20).
12 In general, censuses were considered bad because people could more easily trust in their numbers than in God (2 Sam 24:1-10). However, in this case the census gave the opportunity to collect atonement money from each person. This was a sacrifice of money instead of animals or foodstuffs, but it was not consumed on the altar or by the priests.
13 A half-shekel was approximately 5.7 grams of silver.
15 In God's eyes we are all of equal value. It makes no difference if we have few or many possessions, or what our standing in the community is.
16 Another purpose of this tax was to provide maintenance money for the tabernacle. A well-maintained tabernacle would be visible evidence of the atonement of their souls.
21 The sacrifices in Exo 29:10+ cleansed the spirit, which is the most important thing for a priest. But God also demands that His priests minister before Him with clean bodies as well.
32 God's "patented" anointing oil was to be used only on those people and things that were directly related to the tabernacle. Anointing oil was to signify God's chosen leaders (either priestly or kingly, Isa 61:1). Anointing oil also represents the presence of the Holy Spirit (1 Sam 16:13, Acts 10:38).
33 Infringement or improper use of anointing oil meant exile from God's chosen people. God demands respect for the items He has declared sacred.
37 As with the anointing oil, the sacred incense was to be used exclusively for use in the tabernacle, not to cater to the vanity of men.