Commentaries:
Robertson's Word Pictures (NT)
Whom withstand (w antisthte). Imperative second aorist active (intransitive) of anqisthmi; same form in James 4:7, which see. Dative case of relative (w). For the imperative in a subordinate clause see verse I Peter 5:12; II Thessalonians 3:10; II Timothy 4:15; Hebrews 13:7. Cowardice never wins against the devil (II Timothy 1:7), but only courage.
Steadfast in your faith (stereoi th pistei). Locative case pistei. Stereov is old adjective for solid like a foundation (II Timothy 2:19).
The same sufferings (ta auta twn paqhmatwn). An unusual construction with the genitive rather than the usual ta auta paqhmata, perhaps as Hofmann suggests, "the same tax of sufferings" ("the same things in sufferings"). Probably this is correct and is like Xenophon's phrase in the Memorabilia (IV. 8. 8), ta tou ghrwv epiteleisqai (to pay the tax of old age).
Are accomplished (epiteleisqai). Present (and so process) middle (you are paying) or passive (is paid) infinitive of epitelew, old verb, to accomplish (II Corinthians 7:1).
In your brethren who are in the world (th en tw kosmw umwn adelfothti). Associate-instrumental case adelfothti (in N.T. only here and I Peter 2:17, which see) after ta auta (like I Corinthians 11:5) or dative after epiteleisqai. Even so eidotev (second perfect active participle of oida) with an infinitive usually means "knowing how to" (object infinitive) as in Luke 12:56; Philippians 3:18 rather than "knowing that" (indirect assertion) as taken above.
Other Robertson's Word Pictures (NT) entries containing 1 Peter 5:9:
Galatians 3:3
Colossians 2:5
2 Timothy 2:19
DISCLAIMER: Church of the Great God (CGG) provides these resources to aid the individual in studying the Bible. However, it is up to the individual to "prove all things, and hold fast to that which is good" (I Thessalonians 5:21). The content of these resources does not necessarily reflect the views of CGG. They are provided for information purposes only.