Jeremiah here digresses to notice the attempt on his life plotted by his townsmen of Anathoth. He had no suspicion of it, until Jehovah revealed it to him (Jer 12:6).
the Lord ... thou - The change of person from the third to the second accords with the excited feelings of the prophet.
then - when I was in peril of my life.
their doings - those of the men of Anathoth. His thus alluding to them, before he has mentioned their name, is due to his excitement.