Some Jews today use Shaddai as an acronym for Shomer Daltot Yisrael, “Guardian of Israel’s doors.”
Today an Orthodox Jew would not read the words of Psalm 125:1-2 as they’re written: “Those who trust in the Lord are like Mount Zion, which cannot be moved, but abides forever. As the mountains surround Jerusalem, so the Lord surrounds His people from this time forth and forever.” Fearful of using “the Lord’s name” in vain, they will often replace “the Lord (Yhwh)” with “HaShem,” simply meaning “the Name.” But rather than trusting in the name of the Lord, many place their trust in mezuzot. The word comes from the Hebrew for “doorpost” and is intended to fulfill the Lord’s direction to His people concerning the law, “You shall write them on the doorposts of your house and on your gates” (Deut 6:9). A mezuzah is a small box holding a parchment containing Deuteronomy 6:4-9 and 11:13-21. On the outside of the box is often the letter shin, the first letter of the name Shaddai, the Almighty. Shin looks somewhat like our U with an added vertical line through it. However, instead of generations to come embracing the truth of these words, “As the mountains surround Jerusalem, so the Lord surrounds His people from this time forth and forever” (Ps 125:2), they increasingly thought of these mezuzot as good luck charms fending off evil. However, to our amazement we discover that Jerusalem from above actually looks like the letter shin, representing Shaddai, the Almighty! The left arm of the U follows the Hinnom Valley and the right arm, the Kidron. The middle line is the Tyropoeon Valley through the heart of the city. The mountains from right to left are Olivet, Moriah, and Zion. Carved into the landscape is the Creator’s reminder that, if we will trust HIM, we will find Him trustworthy “forever” (vv 1-2).