Why fear and worship God

And now, Israel, what does the Lord your God ask of you but to fear the Lord your God, to walk in obedience to him, to love him, to serve the Lord your God with all your heart and with all your soul, and to observe the Lord ’s commands and decrees that I am giving you today for your own good? To the Lord your God belong the heavens, even the highest heavens, the earth and everything in it. Yet the Lord set his affection on your ancestors and loved them, and he chose you, their descendants, above all the nations—as it is today. Circumcise your hearts, therefore, and do not be stiff-necked any longer. For the Lord your God is God of gods and Lord of Lords, the great God, mighty and awesome, who shows no partiality and accepts no bribes. He defends the cause of the fatherless and the widow, and loves the foreigner residing among you, giving them food and clothing. And you are to love those who are foreigners, for you yourselves were foreigners in Egypt. Fear the Lord your God and serve him. Hold fast to him and take your oaths in his name. He is the one you praise; he is your God, who performed for you those great and awesome wonders you saw with your own eyes. Your ancestors who went down into Egypt were seventy in all, and now the Lord your God has made you as numerous as the stars in the sky.
Deuteronomy 10:12‭-‬22 NIV
https://bible.com/bible/111/deu.10.12-22.NIV