Honor all people, love the brotherhood, fear God, honor the king. – 1 Peter 2:17, NAS
Does ‘agape’ love demand something higher and nobler from us than ‘philadelphia’ (brotherly love) in our relationships with other believers?
Nine times in his first letter the Apostle Peter employs various words denoting ‘love’. They occur in the following verses: 1:8 (verb, agapate), 1:22 (noun, philiadelphian & verb, agapisate), 2:17 (verb, agapate of the brotherhood), 3:8 (participle, philadelphoi), 3:10 (infinitive, agapan of life), 4:8 (nouns: agapene & agape), and 5:14 (genitive, “a kiss of agapese”). In two instances he uses the noun form or participle of ‘philadelphia’. In one case (2:17) Peter calls for “agapate of the brotherhood.” The other five occurrences are forms of the noun, agape, or of the verb, agapao.
Although the New Testament records no command that we show brotherly love to Christians (or phileo toward God), perhaps too much has been made of a qualitative distinction between these two manifestations of love among members within the church. As most of us know, agape love finds its origin in God first and foremost – as John 3:16, 1 John 3:16, and 1 Jn 4:7-10 make abundantly clear. Agape acts to secure what is best for others, irrespective of whether they are worthy to be so loved. But the apostles (and other New Testament authors) assume the necessity and practice of brotherly love among believers as an expression of the affection of Christ Jesus, who cherishes his people through them (Php 1:8), in order to affirm, encourage and unify his Body in a harmony of mutual regard. This seems to be the case in 1 Peter 1:22 and 3:8. What the apostles do not command is most certainly what they commend (Rom 12:10; 1 Thess 4:9-10; Hebrews 13:1)
Possibly our definition of phileo is limited to a tender, familial affection for someone to whom we are somehow related. It is worth noting that Paul issues a dire warning to those who “do not philei the Lord” (that a curse is laid on them) in 1 Cor 16:22. And in that remarkable passage from John’s gospel (21:15-17), Peter professes (only) philo toward his Master, when the Lord asks him twice: “Peter, do you agapas me?” But (R.C.) Trench writes (according to W.E. Vine, Expanded Expository Dictionary, 694) that the verb for love in Peter’s response “conveys the thought of cherishing the object (Christ) above all else” and of his constant affection from “motives of the highest veneration.” In a Christian context we may understand phileo as no ‘second class love’ but rather an affective, loyal expression of the spiritual bonding of believers, who have a mutual heavenly Father, to one another through the Holy Spirit.
Is it harder to agapao a brother or sister in the Lord than to show them steady brotherly affection (Rom 12:10)? I think not. While the former must come from God and He commands it, our Lord also inspires the latter. By the gracious outflow of His Spirit, philadelphia refreshes others in the Body. The practice of brotherly love among diverse and disparate personalities, whom the Lord has placed in one family, manifests a new heart of flesh (Ez 18:31, 36:26) given to each of us by the Holy Spirit. God instills both kinds of love in His children. By their practice all are blessed (Psm 133).
 Greek words as discussed above are only approximate transliterations of their spellings in the Greek language.