וּלְגָ֣ד אָמַ֔ר בָּר֖וּךְ מַרְחִ֣יב גָּ֑ד כְּלָבִ֣יא שָׁכֵ֔ן וְטָרַ֥ף זְר֖וֹעַ אַף־קָדְקֹֽד׃
갓에 대하여는 일렀으되 갓을 광대케 하시는 자에게 찬송을 부를지어다 갓이 암사자 같이 엎드리고 팔과 정수리를 찢는도다
Rashi
ברוך מרחיב גד BLESSED BE HE THAT ENLARGES GAD — this teaches us that Gad’s territory extended far eastward (Sifrei Devarim 355:2).
Chizkuni
מרחיב גד, “Who enlarges Gad; Moses blesses him to whom G-d had given a large territory, suitable for raising sheep and cattle.
Da'at Zekenim
ברוך מרחיב גד, “blessed be he who enlarges the territory of the tribe of Gad.” Seeing that the ancestral land allotted to Gad was suitable for grazing rather than planting crops, this root is more appropriate for describing expansion. Compare also Hoseah 4,16: “עתה ירעם ה' ככבש בשמרחב, “now the Lord will graze him on the range like a sheep.”