Phil Connors has lived through the same day so many times that he's convinced he's a god. After all, some of the major signs are there. He knows absolutely everything and can't die. That sounds a lot like a god.
PHIL: I'm not the God, I don't think.
Phil knows that he's immortal and almost omniscient (all-seeing). But he's not crazy enough to think he's the one all-powerful God. If that were the case, he'd probably have the ability to just point at things and make them explode, and he's not there just yet.
RITA: You're not a god. Believe me. This is twelve years of Catholic school talking.
Rita thinks it's insane for Phil to talk as though he's some sort of god. After all, she spent her childhood in Catholic school and her religion believes there can only be one true God.
PHIL: Maybe the real God uses tricks. Maybe He's not omnipotent. He's just been around so long He knows everything.
When Rita accuses Phil of using tricks to show he's a god, Phil suggests that maybe the real God just uses tricks to. When you think about it, the real God doesn't need to have infinite power to be a god. He just needs to know an awful lot more and have more power than any regular person.
PHIL: I wake up every day right here in Punxsutawney […] and there's nothing I can do about it."
Phil's ability to live the same day over and over makes him feel both powerful and powerless at the same time. On the one hand, he can do anything he wants because there are no consequences. On the other hand, he feels like nothing he does matters because there are no consequences.
LARRY: He was a really great guy.
After Phil has died (for the thousandth time), his cameraman Larry says a few nice (and sarcastic) words about him. But the truth is that Phil has been a total jerk for most of his life and people aren't really going to miss him all that much. That's why it's crucial for Phil to turn it all around by being nicer.
PHIL: Who wants coffee? Get it while it's hot.
Phil eventually decides that the only way he can make Groundhog Day seem meaningful is if he starts acting nice to all the people around him. Little does he know that this strategy is what will eventually break his curse.
DOCTOR [referring to the dead homeless man]: He was just old. It was just his time.
A big part of Phil's journey comes when he realizes that despite all his power, there are some things he can't change. No matter how many times he tries, for example, he can't save the old homeless man who always dies on Groundhog Day no matter what Phil does.
NURSE: Sometimes people just die.
When Phil confronts the nurse, he wants to know exactly how the old homeless man has died. He wants to know because he thinks he might be able to prevent the man's death the next time he lives through Groundhog Day. But nothing he does ever works. The man is destined to die.
PHIL: It was the end of a very long day.
When Phil finally makes it to February 3rd, he makes the understatement of the century by saying he had a long day the day before. Various people have suggested that by the end of this movie, Phil has spent more than ten years reliving Groundhog Day. That's a lonnng time.