Parshat עקב is probably the strongest Parsha in the Torah in terms of outright Mussar, guiding us how to live. There are numerous ideas mentioned that are designed to give us the proper perspective on life.
We must never forget how fragile man really is. All is temporary and we are constantly placed at Hashem's mercy. We must never get carried away with whatever it is that we achieved in our lives because it is Hashem that is נותן חיל, which means that He allowed for the successes to happen. Without Hashem's influence and guidance, we would not be able to accomplish anything.
We are also reminded that we must never feel a sense of entitlement, or in Hebrew we say, מגיע לי. Moshe makes a point that the nation has been rebellious from the day he met them. Whatever we have is only because of Hashem's kindness, and not because we deserve it.
Our holy Rabbis have a saying, אין אדם מורד לפני הקדוש ברוך הוא אלא מתוך שביעה, that man only rebels against G-d when he is filled up. When he feels he has it all, he doesn't need G-d. It is a challenge to always cleave to Hashem in good times as well as bad. But studying the message of עקב helps give us a little perspective.