Business Rule to update the field with current date and time

Hello Guys,

When ever a record gets inserted on incident table a datetime field is populated with current date and time.

I have a field on the incident form which has type date/time.

For that I have created the Before Business rule of insert type. Below is my code:-

// Add your code here
var dateTime = new GlideDateTime();
current.setValue('u_request_received_date',dateTime);
current.update();

Now I don't want to use current.update() method. And if I remove this, it does not work. 

Please help me with this one 😞 

Note: I need to use only Business Rule.