I have a Payne 394gaw furnace whose pilot ignition sparks forever but the pilot doesn't light. What do I need to do?

Several possibilities. Is the gas shut off valve turned on? Is gas valve in the furnace on? If yes to both & presuming you have gas, I suspect a dirty pilot burner.

Yes, the gas shut off is ON. Gas knob is turned to ON. I also hear the whisper of gas that accompanies the spark, but I do not smell any natural gas. I had also taken off the pilot and spark assembly and made sure there was nothing that was plugging it up and put it back on.

I would be very surprised if you could hear the gas. Either the gas valve is not opening or the pilot oricfice is plugged. I suggest removing the pilot assembly & try blowing it out with canned air or a solvent such as brake or carb cleaner. If you use a solvent, make sure the assembly is completely dry inside & out before reinstalling.

I have exactly the same problem. Gas is flowing for sure as I can hear it and ignite it with a fire lighter.
Did anybody figure out how to rectify this issue? Did cleaning help?