{Knowing} (eidotes). Second perfect active participle of
oida, causal participle. The appeal is to an elementary
Christian belief (Hort), the holiness and justice of God with the
added thought of the high cost of redemption (Bigg). {Ye were
redeemed} (elutr(9374)h(8874)e). First aorist passive indicative of
lutro(935c), old verb from lutron (ransom for life as of a slave,
 Mt 20:28 ), to set free by payment of ransom, abundant examples
in the papyri, in N.T. only here,  Lu 24:21  Tit 2:14 . The
ransom is the blood of Christ. Peter here amplifies the language
in  Isa 52:3f . {Not with corruptible things} (ou phthartois).
Instrumental case neuter plural of the late verbal adjective from
phtheir(935c) to destroy or to corrupt, and so perishable, in N.T.
here, verse  23  1Co 9:25  15:53f.  Ro 1:23 . Arguri(9369) (880a)chrusi(9369) (silver or gold) are in explanatory apposition with
phthartois and so in the same case. Slaves were set free by
silver and gold. {From your vain manner of life} (ek t(8873) mataias
hum(936e) anastroph(8873)). "Out of" (ek), and so away from, the
pre-Christian anastroph(885c) of verse  15 , which was "vain"
(mataias. Cf.  Eph 4:17-24 ). {Handed down from your fathers}
(patroparadotou). This adjective, though predicate in position,
is really attributive in idea, like cheiropoi(8874)ou in  Eph 2:11 
(Robertson, _Grammar_, p. 777), like the French idiom. This
double compound verbal adjective (pater, para, did(936d)i), though
here alone in N.T., occurs in Diodorus, Dion. Halic, and in
several inscriptions (Moulton and Milligan's _Vocabulary_;
Deissmann, _Bible Studies_, pp. 266f.). The Jews made a wrong use
of tradition ( Mt 15:2ff. ), but the reference here seems mainly
to Gentiles ( 1Pe 2:12 ).