Charles Ellicott Commentary Nahum 1:11

"There is one gone forth out of thee, that deviseth evil against Jehovah, that counselleth wickedness." — Nahum 1:11 (ASV)

Come out of you. —Another possible rendering is, He has retired from you [i.e., Jerusalem], who imagines... We prefer the rendering of the Authorised Version, and regard the verse as addressed to Nineveh. The reference in the verses following is sufficiently plain for us to identify this enemy of God with Sennacherib. (Compare the language used by his envoy Rabshakeh in 2 Kings 18:19)