I am installing a lighting fixture in my bathroom , the existing wires are: (1) White that has red paint on it that runs straight thorough the j box and on down to the outlet below... this wire did not have anything from the old fixture connected to it. (1) All White wire that was connected to the old fixture and this continues down to the outlet below as well. (1) Blue wire that was connected to the old fixture but this wire does not continue to outlet below. On the new fixture I have a black, white and a Ground wire. My old fixture did not have a ground wire, as it was so old. Please let me know what you think, any help would be much appreciated.

Thank you
David

Dgarza... I would expect based on your description that the white wire with red paint is an un-switched hot
As it only goes to the outlet below. The blue wire I hope is connected to the switch that turns the light on. The white wire sounds like the neutral connected to both the light fixture and outlet.
The new fixture black would connect to the blue, the new fixture white to the white... you did not mention if you had a ground wire available but if so connect the fixture ground to it.
So now... if you don't have a ground available you will need to either install one or connect this circuit to ground fault interrupter which is permitted by the NEC...

Please be safe, turn the power off, connect the ground or a GFCI..