It is said in the name of Rav Haim Vital (1543-1620), "Mahaloket Ahat Dohe Me’a Parnasot" – "One argument deters one hundred sources of livelihood." What this means is that peace is a conduit of material blessing. Regardless of one’s efforts to earn a living, the presence of "Mahaloket" – strife and discord – will prevent the blessing of Parnasa (livelihood) from being bestowed.
Through our prayers and Misvot, we try to combine the two divine Names of "Havaya" ("Y-H-V-H") and "Adnut" ("A-D-N-Y"). The Name of "Adnut" represents the divine attribute of harsh judgment, and we seek to "sweeten," or alleviate, the judgment by combining this Name with the Name of "Havaya," which signifies the attribute of kindness. This is why one should have in mind the combination of these two Names, and their combined numerical value of 91 ("Havaya" has the numerical value of 26, and "Adnut" has the value of 65). This combination eliminates the potentially harmful effects of God’s strict judgment. However, if one establishes and maintains peaceful relations in his home and with his friends, neighbors and colleagues, he accomplishes much more than simply eliminating the strict justice; he causes the combination between "Havaya" and "Adnut" to multiply exponentially. If we multiply each letter of the Name of "Havaya" by the corresponding letter in the Name of "Adnut" ("Yod" and "Alef," "Heh" and "Dalet," "Vav" and "Nun," "Heh" and "Yod"), we arrive at the products 10 (10*1), 20 (5*4), 300 (6*50), and 50 (5*10). The sum of these four products is 380 (10+20+300+50). The numerical value of the word "Shalom" is 376 (300+30+6+40), and if we add four to represent the four letters of the word ("Shin," "Lamed," "Vav," "Mem"), we arrive at 380. "Shalom," then, is the product – not just the sum – of "Havaya" and "Adnut." Peace has the effect of multiplying the combination of these two divine Names. If a person lives in peace with his family and peers, he not only eliminates the harmful effects of harsh judgment, but multiplies the blessing achieved thereof exponentially.
The Mishna famously comments, "The Almighty found no better receptacle to hold blessing than peace." A person can purchase $250 worth of groceries in the supermarket, but they will not help him without bags with which to bring them home. Somebody can offer us the most flavorful and highest quality wine in the world, but without a bottle we have no means of enjoying it. The same is true of God’s blessings. Even if we are worthy of material blessings, they cannot come down from the heavens without some kind of receptacle. And the Sages teach us that the receptacle that holds the blessing of Parnasa, the conduit through which these blessings are sent to this world, is "Shalom," peaceful relations. And the more peace a person achieves, the more "pipes" he makes available to bring down the "Shefa" (God’s abundant blessings) from the heavens.
It is therefore critical for us to include peace in our efforts to earn a livelihood – peace in our homes, families and communities – so that we will be able to bring God’s blessings upon us and experience prosperity and success.
