Through Silvanus, our faithful brother, as I consider him, I have written to you briefly, exhorting, and testifying that this is the true grace of God in which you stand.
a faithful brother unto you, as I suppose: Silas evidently was well known for fidelity in his many travels with Paul, and now in his travels into Asia Minor. Peter, having worked with him since Paul’s death, "reckons" or "accounts" Silas to be faithful. The word does not indicate doubt.