Can learning or knowing Hebrew be illegal in Lebanon?

No. Hebrew is even taught in the Lebanese University as part of the curriculum for those studying arabic literature. It is an elective course and students can choose between hebrew and persian and syriac. read more

Most people can't distinguish Hebrew, they'd take it as an alien language just like Armenian German or I don't know what. Nevertheless, fact that Israel occupied a part of southern Lebanon for a long time, ties between that occupied area and Israel were strong, people would go and come to Israel every day. read more

Lebanese authorities know that many tourists have been to Israel before coming to Lebanon and they also know that a lot will travel after visiting Lebanon to Israel via Jordan, despite that that don't ask questions about whether you have been to Israel or whether your next destination is Israel, they even don't investigate with you unless they see a document in your luggage related to Israel even if it is a travel guide, so avoid such type of documents. read more