מוֹלִיכָ֖ם בַּתְּהֹמ֑וֹת כַּסּ֥וּס בַּמִּדְבָּ֖ר לֹ֥א יִכָּשֵֽׁלוּ׃
Który wiódł ich przez głębie jako rumaki, po stepie, a szwanku nie ponieśli.
Rashi on Isaiah
like a horse in the desert which does not stumble since it is smooth land, so they did not stumble in the deep.
Ibn Ezra on Isaiah
In the wilderness, which is upon dry land.21I. E. divides the verse into two sentences, He led them through the deep, and He led them, (to be supplied) in the wilderness, or, in the plain, while, according to others, the verse contains only one sentence, He led them through the deep, as a horse (is safely led) in the wilderness.