Rashi: It says about Avraham "Ki Atah Yadati Ki Yerei Elokim Atah" (Bereishis 22:12), and he promised him "Varech Avarechecha" (ibid., 17).

R. Yonah: His Yir'ah is secure and his Pachad is serene.

Malbim: Chachmah itself without Yir'as Hashem does not last - one whose fear of sin precedes his Chachmah, (his Chachmah endures; if not it does not last). If there is no fear, there is no Chachmah (Avos 3:12, 17). Even if he knows the laws of Chachmah, there are pitfalls around in the depths of his Nefesh evil desires and images. He can easily falter from its Chukim. Only Yir'as Hashem will tie the powers of his Nefesh with Musar, so he never veer from the laws of Chachmah. His trust in the laws of Chachmah that he gathered in his Nefesh is not a strong trust, for the besiegers of the city will easily conquer the fortress; they built great strongholds against it. However, if his fear of sin precedes his learning, this is a strong assurance; his Chachmah endures (Avos 3:12).

Rashi: He shelters his sons, via his merit.

R. Yonah: Bitachon is more than Machseh - "Tov Lachasos ba'Shem mi'Vto'ach ba'Adam" (Tehilim 118:8).

Malbim: "Mi Zeh ha'Ish Yerei Hashem Yorenu b'Derech Yivchar;