{By faith in his name} (	(8869) pistei tou onomatos autou).
Instrumental case of pistei (Aleph and B do not have epi) and
objective genitive of onomatos. {His name} (	o onoma autou).
Repeats the word name to make the point clear. Cf. verse  6 
where Peter uses "the name of Jesus Christ of Nazareth" when he
healed the man. {Made strong} (estere(9373)en). Same verb used in
verse  7  (and  16:5 ). Nowhere else in the N.T. Old verb from
stereos, firm, solid. {Through him} (di' autou). Through
Jesus, the object of faith and the source of it. {Perfect
soundness} (holokl(8872)ian). Perfect in all its parts, complete,
whole (from holos, whole, kl(8872)os, allotment). Late word
(Plutarch) once in LXX ( Isa 1:6 ) and here alone in the N.T.,
but adjective holokl(8872)os, old and common ( Jas 1:4  1Th 5:23 ).