You could use the internal pull-up, but it shouldn't be necessary if the pin is
bi-directional.

The example in your PBP manual uses a pull-up on RA4 of the PIC16F84 only
because this pin is an open drain type output, and can only provide ground to
the LCD RS pin.

Look on the MeLabs site for the LAB-X4 examples. They have schematics &
sample code for creating a serial LCD driver with a PIC16F676.