Southward - Rather, "by the Negeb," or south-country; a well-defined tract of territory forming the southernmost and least fertile portion of the land of Canaan and of the subsequent inheritance of Judah. It extended northward from Kadesh to within a few miles of Hebron, and from the Dead Sea westward to the Mediterranean (see especially Joshua 15:21-32).
Into the mountain - The hill-country of southern and central Canaan, mostly within the borders of Judah and Ephraim. It commences a few miles south of Hebron, and extending northward to the plain of Jezreel, runs out eventually northwest-ward into the sea in the headland of Carmel.

And Moses sent them to spy out the land of Canaan,.... He sent them from Kadeshbarnea, as Caleb affirms, Joshua 14:7,
and said unto them, go ye up this way southward; pointing as it were with his finger which way they should go, even up such a hill southward; and which, as Aben Ezra observes, was not the south of the camp, but the south of the land of Canaan; and who further observes, that it is well known that Egypt, from whence the Israelites now came, was to the south of the land of Israel, of which this is a demonstration; the latitude of Egypt is less than thirty degrees, and the latitude of Jerusalem is thirty three, and the wilderness of Paran was in the south of the land of Egypt: it should be rendered by "the south", as in Numbers 13:22; or from the "south" (p), since the Israelites must go northward, as a learned man (q) observes, to enter into the land of Canaan: now this south part of Canaan afterwards belonged to the tribe of Judah, and lying southward, and mountainous, was dry and barren, Joshua 15:1; and was, as Jarchi says, the dregs of the land of Israel; and here, as he observes, the same method was taken as merchants do, who, when they show their goods, show the worst first, and then the best:
and go up into the mountain; which was inhabited by the Amorites, Deuteronomy 1:44; and was afterwards called the mountainous or hill country of Judea, Luke 1:39.
(p) "per meridianam plagam", V. L. "hac meridiana plaga", Junius & Tremellius, Piscator. (q) Bishop Clayton's Chronology of the Hebrew Bible, p. 392.

Get you up this way . . . , and go up into the mountain--Mount Seir (Deuteronomy 1:2), which lay directly from Sinai across the wilderness of Paran, in a northeasterly direction into the southern parts of the promised land.

Southward - Into the southern part of Canaan, which was the nearest part, and the worst too, being dry and desert, and therefore fit for them to enter and pass through with less observation. Into the mountain - Into the mountainous country, and thence into the valleys, and so take a survey of the whole land.