Is it permissible to continue chatting via "Messenger" with a committed young man, limiting the conversation to religious and political matters, while avoiding delving into any topics that violate Islamic manners and morals?

It is not permissible for a woman to speak with a non-mahram young man without need or necessity, due to fear of temptation. Speaking with him about political or religious matters is not considered a need or necessity; rather, it is a step among the steps of Satan by which he lures both parties into the forbidden.