In 2 Nephi 5:10 we read:
And we did observe to keep the judgments, and the statutes, and the commandments of the Lord in all things, according to the law of Moses.
Would we expect Joseph Smith with his limited education to use language like this? Wouldn’t we expect him to simply say they kept the commandments? This list of similar legal terms also occurs in other places in the Book of Mormon and resembles 1 Kings 2:3:
And keep the charge of the Lord thy God, to walk in his ways, to keep his statutes, and his commandments, and his judgments, and his testimonies, as it is written in the law of Moses, that thou mayest prosper in all that thou doest, and whithersoever thou turnest thyself:
How would Joseph know of the difference between statutes, commandments and judgments in the law? Do casual readers of the Bible usually notice this kind of language?