Most LDS consider the word "exactness" a symbolic totem of sorts. It represents temple commitments and how they are to live out their lives.
I searched the word "exactness" in my Gospel Library app. In the Old Testament, there were zero citations using the word "exactness". However the word "exact" occurs once in the Epistle Dedicatory, and reflects an idea synonymous with the word "specific". After that, the word "exact appears four times. The word "exacted" appears twice. "Exaction" occurs twice. In every case, outside the Epistle Dedicatory, it refers to taxation or collection of moneys or debts.
In the New Testament, only the word "exact" appears, and only one time. Also referring to the tax collector (AKA "publican") collecting no more than he is required.
In the Book of Mormon, here is the count:
I searched the word "exactness" in my Gospel Library app. In the Old Testament, there were zero citations using the word "exactness". However the word "exact" occurs once in the Epistle Dedicatory, and reflects an idea synonymous with the word "specific". After that, the word "exact appears four times. The word "exacted" appears twice. "Exaction" occurs twice. In every case, outside the Epistle Dedicatory, it refers to taxation or collection of moneys or debts.
In the New Testament, only the word "exact" appears, and only one time. Also referring to the tax collector (AKA "publican") collecting no more than he is required.
In the Book of Mormon, here is the count:
- exact - 1
- exacted - 1
- exactness - 1
The use of "exactness" is the only one which refers to something other than taxes or collection of monies. However it is completely possible that the word exactness did refer to the traditional use of the word, however in our modern reading we equate the word with "precise" or "specific". A linguistic or scripture scholar might be able to consider an alternate meaning for this.
Doctrine and Covenants uses the word "exactly" three times, all in Official Declaration 1. All cases refer to a definition synonymous with the word "specific, precisely".
The Pearl of Great Price uses the word "exactly" one time. It is when Joseph says a pillar of light was exactly over his head.
I find it extremely peculiar that this word is used so infrequently in scripture. The total count comes to 20 times, in various forms, throughout hundreds of pages of scripture.