The Greek verb antagonizomai (ἀνταγωνίζομαι) means to struggle against, to contend with, to strive in opposition — combining anti (against) and agonizomai (to contend/wrestle). It appears once in the New Testament in Hebrews 12:4.
Hebrews 12:4 places the readers' suffering in sobering perspective: "In your struggle against sin, you have not yet resisted to the point of shedding your blood." The author is comparing their trials with the martyrdom of the saints in Hebrews 11. The word antagonizomai frames the Christian life as active combat against sin — not passive endurance but athletic, wrestling opposition. This is the language of the arena. Paul uses the related word agonizomai repeatedly: "I have fought the good fight" (2 Timothy 4:7). Hebrews 12:1–4 as a whole presents Jesus as the supreme example — he "endured the cross, despising the shame" — and calls believers to look to him when their struggle against sin seems overwhelming.