Can my employer blacklist me from entering saudi?i dont want his work

Nothing can happen. You can decline the offer and he can't blacklist you for that. If you are not happy with the T & Cs or the way they act then its probably best to leave. Once in Saudi you are stuck !

So my visa will be cancelled to the embassy of saudi arabia?
Thanks for your reply.

The visa that will be sent from Saudi to a Saudi Embassy in an X country is a generic one, that means it will not carry a certain person name; it will be only carrying the Gender, Profession and Nationality of the potential employee, an example, let's say a visa for a Female Nurse from India. The name and other details of that person will be added by the Saudi Embassy later when that person or the Visa Agency starts the process of issuing the visa.

So to answer you, no he can't even touch you . If he is acting like this before you land here in Saudi, then trust me he is not someone you want to work for.

Trust your inner feeling, if it doesn't feel good walking into it, then don't continue.

i was hired as name hire/direct hire, my employer processed my working visa at saudi arabia and just sent me, meaning i already have the visa but my passport was not stamp yet.

It says Working Visa? and not Business Visa or Commercial Visa ?