"and he did not give to him a nachalah  inheritance  in it nor AD MIDRACH KAF RAGEL  "even enough to put your foot on" Devarim 2:5 ; and yet, even when he had no ben, the havtachah  promise  of Hashem to him was ES HAARETZ HAZOT E'TEN  "this land I will give"  to him and to his zera  seed  after him. [Devarim 2:5; Bereshis 12:7; 13:15; 17:8; 26:3; 48:4]