Easton's Bible Dictionary (1897)/Agony
Agony Contest; wrestling; severe struggling with pain and suffering. Anguish is the reflection on evil that is already past, while agony is a struggle with evil at the time present. It is only used in the New Testament by Luke (22:44) to describe our Lord's fearful struggle in Gethsemane.
The verb from which the noun "agony" is derived is used to denote an earnest endeavour or striving, as "Strive [agonize] to enter" (Luke 13:24); "Then would my servants fight" [agonize] (John 18:36). Comp. 1 Cor. 9:25; Col. 1:29; 4:12; 1 Tim. 6:12; 2 Tim. 4:7, where the words "striveth," "labour," "conflict," "fight," are the renderings of the same Greek verb.