Background: The outbreak of war in Israel on 7 October and the unique events of that day have presented unprecedented challenges to first responders (FRs), who are professionally trained to engage in providing assistance in such circumstances. Moreover, while research demonstrates the long-term psychological consequences of FRs, little is known regarding how FR's engagement in providing assistance relates to stress and resilience levels as events continue to unfold.Objective: The current study examined the relationship between traumatic stress symptoms (TSS) and resilience levels among FRs and controls during the first weeks of the Iron Swords war, while focusing on the moderating role of active engagement in providing assistance.Method: Data were collected during the first month of the Iron Swords war from 374 participants living in Southern Israel, of whom 77 (20.6%) were FRs. All participants filled out scales assessing TSS and resilience and provided relevant background information.Results: High TSS levels were associated with reduced resilience in FRs and non-FRs. Moreover, both the study group and active engagement were significant moderators for the TSS-resilience link, which was insignificant among FRs who provided assistance and for civilians who did not provide assistance. However, the TSS-resilience association remained significant for FRs who did not engage in providing assistance and for civilians who did.Conclusions: Our findings highlight the importance of examining the extent to which FRs act in line with their duties during times of adverse stress. Clinical interventions aimed towards FRs who did not engage in providing assistance are needed and should focus on the extent to which their moral values, beliefs and expectations are met, as these appear critical parameters in preserving resilience.