Hashem's Promise will be fulfilled in its entirety

"Go for yourself from your land, from your relatives, and from your father's house to the land that I will show you" (Bereishit 12:1)

Rashi writes on the words "go for yourself": For your own benefit and for your own good. What is this benefit? "And I will make of you a great nation"; here you will not merit the privilege of having children and there you will, and there you will also become famous.

The commentators write that the words לך לך, go for yourself, have a numerical value of one hundred. When Hashem promised Avraham that he would have children, he was seventy-five years old. Yet this promise was fulfilled only when he reached the age of one hundred, twenty-five years after the promise! This was a not simple test; Avraham and Sara were old and longed for a child and finally they are told they would merit a son. But one year passes, and another year, and they are still waiting. Nevertheless, Avraham does not entertain thoughts about Hashem's ways and does not ask questions about the promise. Only twenty-five years later do they merit salvation when their son Yitzchak is born.

This serves as a lesson for those who come to ask for a blessing for salvation, whether for children or livelihood or any other matter. Often people want to see the fulfillment of the verse "before they call I will answer!" They are not capable of waiting and wish an immediate answer to their prayers. Of course this is not the correct attitude. We see how Avraham waited for twenty-five years, displaying great patience until he merited a child. He had no doubt that Hashem's promise would be fulfilled in its entirety – if not now then sometime in the future, for Hashem knows the most auspicious time to fulfil a petitioner's request.

This is why we conclude the first blessing of the Shemoneh Esrei prayer with the words "Shield of Avraham." Avraham was the example of complete faith in the Creator and cleaved to Him with all his heart because he believed He would watch over him and protect him from any mishap. We mention this in the prayer so we should remember Avraham and learn from his deeds. May it be His will that we indeed merit following in his footsteps.