Also see definition of "By" in Word Study
By [ebd]
in the expression "by myself" (A.V., 1 Cor. 4:4), means, as rendered in the Revised Version, "against myself."
BY [isbe]
BY - In the sense of "against" which survives only in dialectal English (compare Wright, Dialect Dict., I, 470, for examples) is the King James Version rendering of the dative emauto of 1 Cor 4:4 (the American Standard Revised Version renders this "against"). In classical Greek the same idiom sunoida with dative = "be conscious" or "be cognizant of'' a thing.
Also see definition of "By" in Word Study