This research advances the forgiveness literature by identifying genetic and gender predictors that operate through empathy. In a sample of 202 (101 males, 101 females), both the oxytocin receptor gene single nucleotide polymorphism rs53576 and gender had indirect effects on trait forgiveness through trait empathy. Furthermore, rs53576 and gender had indirect effects on state interpersonal forgiveness through trait empathy and state empathy for one’s real-life offender. Simulation-based regression analyses with 10,000 repetitions on an additive model showed stronger evidence for the effect of gender (females > males) than rs53576 (GGs > A-carriers) on most empathy and forgiveness measures. Further, rs53576 effects on empathy were stronger at the state than trait level. Overall, this work advances knowledge of interpersonal forgiveness predictors, shows the importance of balancing gender with sufficient sample sizes in studies of rs53576, points to the value of investigating state empathy effects and demonstrates genetic and gender indirect effects on forgiveness through empathy.