"And if you do not redeem it, you shall break its neck"—Exodus 34:20.
We are commanded to break the neck of a firstborn male donkey—if the owner does not wish to redeem it.
"During the plowing and harvest [seasons] you shall rest"—Exodus 34:21.
We are commanded to abstain from agricultural work during the Shemitah (Sabbatical) Year. This command is repeated in the Torah several times.
This mitzvah, according to biblical law, applies only in the Land of Israel.
"You shall not sow your field"—Leviticus 25:4.
It is forbidden to sow the fields during the Shemitah (Sabbatical) Year.
"You shall not prune your vineyard"—Leviticus 25:4.
It is forbidden to do agricultural work on fruit trees during the Shemitah (Sabbatical) Year.
"That which grows of its own accord of your harvest, you shall not reap"—Leviticus 25:5.
It is forbidden to harvest – in normal fashion – that which grows wild in the fields during the Shemitah (Sabbatical) Year. One may only harvest it as if it was ownerless, i.e. without extensive preparation or arrangement, and not in bulk.