This formula always introduces a very emphatic saying. More tolerable for the land of Sodom, etc. These cities did not have the opportunity, and hence, not the responsibility, of those to which Christ or his apostles preached. As sheep in the midst of wolves. Be wise as serpents.
Serpents are very cautious in avoiding danger.
Harmless as doves. Guileless and innocent as doves. The dove, peaceful, never preying on other birds, has always been a symbol of innocence. Beware of men. To the local courts to be tried for heresy and other offenses.