Special Caracter In Update

I made a stored proc for update fields in a table everything is correct but when my new field contains a special caracter like *,/,[, ' , and a space too i have an error. I wrote it and i don't understand why it doesn't work.

CREATE PROCEDURE [sp_modif](@ID varchar(100),
@Table varchar(100),
@NewId varchar(100),
@CUSTOMER varchar(100),
@NewCUSTOMER nvarchar(255))

DECLARE @Commandvarchar(8000)
SELECT @Command = "UPDATE "+@Table+" SET ["+@CUSTOMER+"] = '"+@NewCUSTOMER+"' where ID like "+@NewId
execute (@Command)

Thank you