The heavenly purpose...
The heavenly purpose, however, was not to confine the faith within tribal or national borders. The Most Merciful and Compassionate planned to spread the faith throughout the world and to show all mankind the right path. The Almighty administers the universe through the usual and natural courses and subjects all the events of the world to the law of cause and effect.
He preserved the revealed faith and kept it alive, though at a standstill, through a small community, which was blessed by inheriting that faith from its holy father. He caused that faith to inflame and spread when that community grew and acquired a power adequate to the great task of spreading the faith. That small community was destined to grow through two lines, the Ishmaelite and the Israelite.
Both of them were blessed and both were tested and commissioned with the great task of preserving and spreading the faith, but the two tests were not simultaneous. Though Ishmael was the first son of Abraham and acquired a heritage of faith and blessing like that of his brother Isaac, God put off the test of his descendants for many centuries. He was preparing them to continue the mission which the descendants of Isaac had started.
To begin with the line of Isaac, the Almighty God established a covenant with him. From the Old Testament: “As for Ishmael, I have heard you; behold, I will bless him and make him fruitful and multiply him exceedingly; he shall be the father of twelve princes, and I will make him a great nation. But, I will establish my covenant with Isaac, whom Sarah shall bear to you at this season next year.” Genesis, Chapter 21.
Wilson : According to your statement, the heavenly purpose was not to confine the faith to one or two communities or nations but to spread the true faith throughout the world and to introduce the heavenly principles to all nations. This, however, does not seem to be the case. The Old Testament repeatedly calls the Israelites God's chosen people. It calls the other people gentiles. This shows that the Israelites were the main concern of the heavenly message.
Chirri : With the covenant which was established between God and Isaac, the children of Israel were supposed to embrace and follow sincerely the heavenly instructions and to lead the rest of the nations to the path of God. But the Israelites did not live up to this expectation.