the head, and not the tail. Figure of speech Pleonasm (App-6) for great emphasis.
above... and not beneath. Figure of speech Pleonasm. See note above.
Related Commentaries of Deuteronomy 28:13
Deuteronomy 28:13
13 And the LORD shall make thee the head, and not the tail; and thou shalt be above only, and thou shalt not be beneath; if that thou hearken unto the commandments of the LORD thy God, which I command thee this day, to observe and to do them: