The Rabbeinu Yonah writes, "Hashem promised that Eretz Yisrael would be Avraham's. But when Sarah was niftarah, Avraham didn't even own a plot of land to bury her! He had to buy one. Even so, Avraham didn't ask questions about Hashem which reveals Avraham's love."
The Rabbeinu Yonah says that this was Avraham's tenth test.
We are more aware of the challenges and tests that are related to deeds, for example, we might know to improve our tefillah, our Torah studies, our speech, etc. But there is another realm in which we must improve and that is with emunah. Avraham's ten tests were about questioning Hashem’s ways.
Rebbe Shimon Yaroslover zt'l was niftar at age ninety-one, which was extremely old in those days. People asked him, "How did you merit to live so long?" He replied, "It's because I never asked questions."
He explained, "When a person asks questions about how Hashem leads the world, Heaven replies, 'Come up to heaven. From up here you will see that everything is for the good.' I never ask questions, so I wasn't called to shomayim to receive answers." (Ohel Shimon p.17).
It states (24:1) את ברך 'וה בימים בא זקן ואברהם בכל אברהם, "And Avraham was old, well on in years, and Hashem blessed Avraham with everything." How did Avraham merit a long life? The Binyan Dovid (47) zt'l says that it was because he never asked questions. Therefore, Heaven didn't have to call him up to show him that everything was good.
By the Shema will live long. But it can also mean באחד המאריך כל, one who focuses on how everything comes from the one Hashem, ושנותיו ימיו לו מאריכין, he will live long.
Tosfos writes that the final letters of אב ןזק םאברה spell ן"אמ, because whoever answers amen merits a long life.
The Midrash states that בכל, "everything" refers to the mitzvah of succah. The Chozeh of Lublin (Avnei Zikaron 662) zt’l explains that the succah reminds us that we can live in a hut for seven days, and it is fine and comfortable. We learn that it is possible to make do with less. When we know this, we have everything. Even a person with few physical possessions can feel satisfied with his lot. But when one chases after luxuries, he always feels lacking.
The Mishnah (Avos 4:1) states, בחלקו השמח עשיר איזהו, "Who is wealthy? One who is satisfied with his portion." Sfas Emes (and other miforshim) say this also refers to one's spiritual portion. We should feel satisfied and happy with whatever mitzvos and spiritual achievements we accomplished. We must strive for more, but at the same time, be satisfied with our level, too.
