Question:
Is it good/permissible to make a deal with Hashem?
Example: "I will learn an hour every shabbos for a month if I get above a 90 on my exam tomorrow"
Thank you
Answer:
We don't make deals with Hashem, with the exception of the mitzvah of giving tzedakah. What you may do is to pledge (bli neder) to learn an hour every shabbos for a month, and daven that in that zechus, Hashem should help you get a good mark on your test.
Sources:
Devorim 6-16, Tractate Ta'anis 9a, Sefer Hachinuch 395.
