This is not acceptable , Personal threats and comments are a sign of his insecurity in his position , he chose a victim and gets off on it , raise a grievance or have a word with someone higher just to log that this has happened, and that the manager has apologised for his behaviour, , i know its old fashioned but there is only one way to stop bullys and that is to stand up for them , i would go off sick and when you contact him say that the personal remarks and threats incident has stressed you out and you have been unable to sleep, he is unlikely to have much to say about that when you have a your return to work interview, but do get his card stamped by logging it with higher management , you may need it if it was to continue..... best of luck !