What semantic notions underlie 'joining together' and 'impose, enjoin'?

I quote Etymonline. To wit, how did

in- "on" (from PIE root *en "in")
+ iungere "to join together" (from nasalized form of PIE root *yeug- "to join")

compound to mean

"impose (on), inflict; subject to; assign (to)"

?


Solution 1:

The first few OED entries tell the tale.

  1. trans. To join together. Obs.

  2. In early use: To impose (a penalty, task, duty, or obligation); said esp. of a spiritual director
    (to enjoin penance, etc.). Hence in mod. use: To prescribe authoritatively and with emphasis (an action, a course of conduct, state of feeling, etc.).

  3. To prohibit, forbid (a thing); to prohibit (a person) from (a person or thing, or some action).
    Now only in Law: To prohibit or restrain by an injunction.

So the way it worked was, first it was just joining together, then it became joining a rule with a person, then it became specialized on the nature of the rule, limiting it to a negative rule -- Don't Do X. Prohibitions have always constituted a pretty prominent variety of rule, after all.
OK?