Scent/smell/odour as covenant symbol

Smell plays an important role in ancient Israelite sacrifice and anointing. Repeatedly in the Pentateuch, the sacrifices are described as "a sweet savour before the Lord" (See Exodus 29:25 for one out of very many examples). In fact, the Hebrew reyach means scent/smell/odour but is also a technical term for a sacrifice. It is very similar to another word, ruach. This is difficult to translate because it has multiple meanings. In the Old Testament, it is translated as wind, breath or spirit. The sacrificial reyach is probably related to it in the sense that it ascends to God like a wind. But there is also another aspect of ruach

Because breath plays such a vital part of our lives, the word ruakh took on additional meanings. Speakers of biblical Hebrew recognized that without the breath of life, we die. It’s an essential part of who we are (e.g., Ps 32:2; 104:29; Isa 26:9). Additionally, our breath is closely linked to various emotional states. We breathe differently when we’re engaged in ruthless passion than when we’re acting with steady and skillful wisdom. So, the Hebrew Bible connects the ruakh with both the core of who we are and different emotional states. Thus, when God describes how courageous Caleb differs from the other Israelite spies too afraid to enter Canaan, God says: “But I’ll bring my servant Caleb into the land that he explored, and his descendants will possess it because he has a different spirit [ruakh], and he has remained true to me” (Num 14:24 CEB). Literally, God’s saying that Caleb has a different breath than the other spies, but the idea is that his inner disposition is different.

-Schlimm, Matthew Richard. 70 Hebrew Words Every Christian Should Know (pp. 47-48). 

To me, this contextualizes the admonition to sacrifice "a broken heart and a contrite spirit" in new ways. The reyach should be done with ruach. The sweet savour before the Lord that came from animal sacrifice is closely related to the core of who we really are. If that is "broken" to align with God's will, our personal sacrifice will "smell" sweet to God. Paul must have had something like this in mind when he said

But I have all, and abound: I am full, having received of Epaphroditus the things which were sent from you, an odour of a sweet smell, a sacrifice acceptable, wellpleasing to God. (Phillippians 4:18)

This theme is prevalent in ancient temple worship, not only for sacrifices but also incense and anointings. Exodus 30 is one of the chapters containing instructions for the tabernacle. Here they are instructed to burn "sweet incense every morning" (v.7) on the altar before the veil. They are instructed to make "holy anointing oil" (v.25) and a perfume (v.35) consisting of aromatic spices. 

The Hebrew word for those aromatic spices is bosem. This word is also found in Isaiah 3, where the "daughters of Zion" (inhabitants of Jerusalem) are warned of the coming destruction because of their pride

And it shall come to pass, that instead of sweet smell there shall be stink; and instead of a girdle a rent; and instead of well set hair baldness; and instead of a stomacher a girding of sackcloth; and burning instead of beauty.

The sweet smell that will be replaced by stink is the "bosem" that compounded the holy anointing oil. This happens when a covenant people turns to pride and idolatry.

Leviticus 26 is another similar prophetic warning of the consequences if the people of Israel turn away from their covenants

And I will make your cities waste, and bring your sanctuaries unto desolation, and I will not smell the savour of your sweet odours. (Leviticus 26:31)

This is referring to the reyach, the sacrifices that God will no longer accept or "smell". The Benson commentary to this verse explains

The incense made of several sweet spices, which was daily offered to God in the sanctuary. These, though when offered to God with faith and obedience they were sweet and acceptable to him, he here threatens he will not smell, or accept, as being presented in hypocrisy and unbelief. The expression is metaphorical, and signifies that neither their prayers nor sacrifices should be accepted.

So what does all this have to do with the Book of Mormon? Reading the accounts of the destruction of the Jaredites and the people in Ammonihah and, this topic of smell comes up.

22 And so swift and speedy was the war that there was none left to bury the dead, but they did march forth from the shedding of blood to the shedding of blood, leaving the bodies of both men, women, and children strewed upon the face of the land, to become a prey to the worms of the flesh.
23 And the scent thereof went forth upon the face of the land, even upon all the face of the land; wherefore the people became troubled by day and by night, because of the scent thereof. (Ether 14)

Nevertheless, after many days their dead bodies were heaped up upon the face of the earth, and they were covered with a shallow covering. And now so great was the scent thereof that the people did not go in to possess the land of Ammonihah for many years. And it was called Desolation of Nehors; for they were of the profession of Nehor, who were slain; and their lands remained desolate. (Alma 16:11)

In both cases the description sounds like a fulfillment of these Old Testament warnings where the sweet savour of sacrifice is gone and replaced with a stink when the covenant people break their covenant. In both cases the dead bodies and the scent covers "the face of the land", a land "preserved for a righteous people" (Ether 2:7). But the Jaredites cast out Ether, the only righteous among them (Ether 13:13), and the people in Ammonihah cast out the righteous in Alma 14:7. When there were no more righteous among them, destruction was inevitable. There was obviously a foul smell from all those dead bodies, but on a deeper symbolic level there was also the stench of iniquity that covered the face of the land.

On a personal level, we can produce a sweet savour (reyach) before the Lord by sacrificing a contrite spirit (ruach). We can be the salt of an earth filled with iniquity, a salt that keeps its savour to preserve the earth from becoming rotten and stinky.