"Why did God choose the Jews?" is what a lady in Bible study asked me recently. My first thought was, "Why did God make the sky blue?" recognizing that the people which became the Israelites were completely made that way by the laws of God, not by themselves (the people thus an arbitrary point). I told her I would try to dig deeper and get back to her next Lord's day. Could it be something as simple as God knowing that the patriarchal laws for the Gentiles would come to a point of hopelessness and that He needed to preserve His will through a specific group He would focus on to be distinguished from the rest of the world? i.e. a seed of people in the soil of the world that would grow into the tree producing His Son? Or might there be more to social and historical considerations? Any thoughts would be most welcome.
God answered that question several times. It all comes down to the fact that He promised Abraham and He kept that promise for His name sake.
"Do not think in your heart, after the LORD your God has cast them out before you, saying, 'Because of my righteousness the LORD has brought me in to possess this land'; but it is because of the wickedness of these nations that the LORD is driving them out from before you. It is not because of your righteousness or the uprightness of your heart that you go in to possess their land, but because of the wickedness of these nations that the LORD your God drives them out from before you, and that He may fulfill the word which the LORD swore to your fathers, to Abraham, Isaac, and Jacob. Therefore understand that the LORD your God is not giving you this good land to possess because of your righteousness, for you are a stiff-necked people" (Deuteronomy 9:4-6).
"Yet the house of Israel rebelled against Me in the wilderness; they did not walk in My statutes; they despised My judgments, 'which, if a man does, he shall live by them'; and they greatly defiled My Sabbaths. Then I said I would pour out My fury on them in the wilderness, to consume them. But I acted for My name's sake, that it should not be profaned before the Gentiles, in whose sight I had brought them out" (Ezekiel 20:13-14).
"Therefore say to the house of Israel, 'Thus says the Lord GOD: "I do not do this for your sake, O house of Israel, but for My holy name's sake, which you have profaned among the nations wherever you went. And I will sanctify My great name, which has been profaned among the nations, which you have profaned in their midst; and the nations shall know that I am the LORD," says the Lord GOD, "when I am hallowed in you before their eyes"'" (Ezekiel 36:22-23).
The same can be said about Christians.
"Blessed be the God and Father of our Lord Jesus Christ, who has blessed us with every spiritual blessing in the heavenly places in Christ, just as He chose us in Him before the foundation of the world, that we should be holy and without blame before Him in love, having predestined us to adoption as sons by Jesus Christ to Himself, according to the good pleasure of His will, to the praise of the glory of His grace, by which He has made us accepted in the Beloved. In Him we have redemption through His blood, the forgiveness of sins, according to the riches of His grace which He made to abound toward us in all wisdom and prudence, having made known to us the mystery of His will, according to His good pleasure which He purposed in Himself, that in the dispensation of the fullness of the times He might gather together in one all things in Christ, both which are in heaven and which are on earth--in Him. In Him also we have obtained an inheritance, being predestined according to the purpose of Him who works all things according to the counsel of His will, that we who first trusted in Christ should be to the praise of His glory. In Him you also trusted, after you heard the word of truth, the gospel of your salvation; in whom also, having believed, you were sealed with the Holy Spirit of promise, who is the guarantee of our inheritance until the redemption of the purchased possession, to the praise of His glory" (Ephesians 1:3-14).
"Now I say that Jesus Christ has become a servant to the circumcision for the truth of God, to confirm the promises made to the fathers, and that the Gentiles might glorify God for His mercy, as it is written: "For this reason I will confess to You among the Gentiles, and sing to Your name." And again he says: "Rejoice, O Gentiles, with His people!" And again: "Praise the LORD, all you Gentiles! Laud Him, all you peoples!"" (Romans 15:8-11).
"Why did God choose the Israelites as His people?" also speaks about this topic.