knoweth. Put by Figure of speech Metonymy (of Cause), for the effect of acting on the knowledge.
turtle. turtle-dove.
Related Commentaries of Jeremiah 8:7
Jeremiah 8:7
7 Yea, the stork in the heaven knoweth her appointed times; and the turtle and the crane and the swallow observe the time of their coming; but my people know not the judgment of the LORD.