Eternal salvation refers to the belief that an individual will spend eternity in heaven with God after they die. It is a concept found in many religions, including Christianity and Islam. The idea is that through faith, repentance, and acceptance of Jesus Christ as their savior, Christians can attain eternal salvation and be granted access to the kingdom of Heaven. This means that an individual's soul will live on forever with God in a state of perfect happiness and bliss, free from sin and suffering.