John Gill Commentary Deuteronomy 28:66

"and thy life shall hang in doubt before thee; and thou shalt fear night and day, and shalt have no assurance of thy life." — Deuteronomy 28:66 (ASV)

And your life shall hang in doubt before you
Whether it shall be spared or not by the enemy:

and you shall fear day and night ;
being in continual dread of being killed:

and shall have none assurance of your life ;
of its being continued a moment scarcely, but live in constant fear and expectation of its being taken away.