XPath query with descendant and descendant text() predicates

I would like to construct an XPath query that will return a "div" or "table" element, so long as it has a descendant containing the text "abc". The one caveat is that it can not have any div or table descendants.

<div>
  <table>
    <form>
      <div>
        <span>
          <p>abcdefg</p>
        </span>
      </div>
      <table>
        <span>
          <p>123456</p>
        </span>
      </table>
    </form>
  </table>
</div>

So the only correct result of this query would be:

/div/table/form/div 

My best attempt looks something like this:

//div[contains(//text(), "abc") and not(descendant::div or descendant::table)] | //table[contains(//text(), "abc") and not(descendant::div or descendant::table)]

but does not return the correct result.

Thanks for your help.