Rashi on Numbers 13:29/רש"י על במדבר י״ג:כ״ט

1עמלק יושב וגו׳ THE AMALEKITES ABIDE [IN THE LAND OF THE SOUTH] — Because they had already been “burnt” by Amalek, the spies mentioned him first in order to terrify them (cf. Midrash Tanchuma, Sh'lach 9).

2ועל ידי הירדן AND BY THE יד OF THE JORDAN — יד means what it literally implies: beside the Jordan. They meant: the Canaanites live on the bank of the Jordan and therefore you will be unable to cross it.