It looks like I didn't finish my train of thought very well. When we find the correct God, we are complete and fulfilled. A false god can give us some comfort just like belonding to a club of model train enthusiasts can give us some satisfaction in life, but being complete takes God and that takes knowing the only true God.
You probably don't notice but those that worship a false god aren't complete and fulfilled. They are worried about getting to Heaven, not about knowing God and having a relationship with him. That doesn't offer a fulfillment, just more questions.
Again, I respectfully disagree. Actually, I'm in agreement with pretty much all of your first paragraph above, but not so much with the second.
I would agree that obviously, if we ever met
THE God, we'd be pretty happy and fulfilled about the experience. Hell, I once got to meet Earl Campbell, the former gifted Hall-of-Fame runningback for the Houston Oilers, and I've been telling that story ever since, anytime someone gives me the chance. Imagine how much more fulfilling it would be to meet God . . . although, I am a pretty big Titans/Oilers fan, so that brush-with-greatness was quite 'Sweeeeeeeet' for me.
However, I disagree that all people who worship false gods or who worship no gods at all lack the appearance of fulfillment and completeness. Some of the happiest, most fulfilled people I've ever met were atheists, or it certainly seemed like it to me. I've also met fulfilled Muslims, many on this site who believe their God, Allah, is the true and correct divine creator of the universe. I've met fulfilled Christians who feel the same way. I've also met practitioners of many others religions who feel fulfilled and blessed though they worship completely different gods altogether.
And here's the deal, I certainly don't mean to be offensive. Seriously, that is not my intent. But I just believe it to be a bit dismissive of the OP and somewhat religiously flippant to say man is 'incomplete' without God. Again, no offense, but that sounds like a pat answer that is far too convenient to be of any real worth to many who are sincerely searching for evidence of the divine but still failing to find it.
I certainly don't mean this toward you, at least not pointedly, but I am often bothered by religious practitioners who reach into their bag of answers and just throw out something meaningless and therefore ultimately worthless to others who are truly, sincerely striving to find evidence of the divine. I don't think we all need 'meaning and purpose', at least not of a God-inspired or religious kind, in our lives to feel contentment and fulfillment. There are many people who feel 'complete' and content in the notion that there is no ultimate meaning, that they are merely animated carbon motivated by electrically-sparked neurons firing in their brains, or something like that.
So, I appreciate your responses, but I respectfully disagree. I think there is certainly more to it than what you have provided. It seems that while 'meaning and purpose' might be part of the reason some people gravitate toward religion and God-models, there is nothing that reasonably explains, much less conclusively proves, that people search for God to be 'complete'. That is just too vague of a term. There are very specific, very definite reasons that people choose to worship gods, or so it seems to me. But, I am always comfortable with the possibility that I might be wrong.