strength (Hebrew #1679)

Deuteronomy
33:25   Thy shoes
man`al (Hebrew #4515)
a bolt
KJV usage: shoe.
Pronounce: man-awl'
Origin: from 5274
shall be iron
barzel (Hebrew #1270)
iron (as cutting); by extension, an iron implement
KJV usage: (ax) head, iron.
Pronounce: bar-zel'
Origin: perhaps from the root of 1269
and brass
nchosheth (Hebrew #5178)
copper, hence, something made of that metal, i.e. coin, a fetter; figuratively, base (as compared with gold or silver)
KJV usage: brasen, brass, chain, copper, fetter (of brass), filthiness, steel.
Pronounce: nekh-o'-sheth
Origin: for 5154
; and as thy days
yowm (Hebrew #3117)
a day (as the warm hours), whether literal (from sunrise to sunset, or from one sunset to the next), or figurative (a space of time defined by an associated term), (often used adverb)
KJV usage: age, + always, + chronicals, continually(-ance), daily, ((birth-), each, to) day, (now a, two) days (agone), + elder, X end, + evening, + (for) ever(-lasting, -more), X full, life, as (so) long as (... live), (even) now, + old, + outlived, + perpetually, presently, + remaineth, X required, season, X since, space, then, (process of) time, + as at other times, + in trouble, weather, (as) when, (a, the, within a) while (that), X whole (+ age), (full) year(-ly), + younger.
Pronounce: yome
Origin: from an unused root meaning to be hot
, so shall thy strength
dobe' (Hebrew #1679)
quiet
KJV usage: strength.
Pronounce: do'-beh
Origin: from an unused root (compare 1680) (probably meaning to be sluggish, i.e. restful)
be.