בראשית ברא אלקים את השמים ואת הארץ (בראשית א:א)

The Midrash  explains the reason why the Torah starts with the letter “ב” since it’s referenced to the word “ברכה” – blessing. Would not the Torah need to start with the letter “א,” which references to the word “אמת” as it says in Tehillim קיט:קס “ראש דברך אמת” – the beginning of Hashem’s words is with אמת.  The word “אמת” is alluded to in the passuk since the end letters of the words בראשית ברא אלקים את spells the word אמת.

Chazal say on the pasuk “אבן שלימה וצדק יהיה לך” מדרש רבה ויקרא או:ז) – the stone weights that you use to measure fabrics should be whole to the exact measurements.  Chazal translates “אבן שלימה – if you will handle dealings ehrlich – scrupulously, then “יהיה לך” – you will have money and you will be able to buy and sell with successful profits.  But if you will not deal ehrlich, then a קללה – curse will go into your money.  We understand from this Midrash  that when one handles his business deals ehrlich, he will see bracha in his earnings, and if the opposite, he does dishonest dealings; then his business will be cursed.

This explanation explains why the Torah starts with an “א” since the letter “ב” represents “ברכה,” which only comes if you deal with אמת וצדק honesty. “

This is also the reason why the Torah finishes with the parsha of וזאת הברכה and starts with בראשית.  In the parsha of וזאת הברכה, it says all the brachos that Moshe Rabbeini blessed the Yidden with and therefore, Parshas Bereishis starts with the letter “ב,” which represents ברכות.