In v. 13, Paul called Jesus Christ “Savior.” That is the title of Christ. Then in v. 14, he explains that Christ “gave himself for us.” That is the work of Christ. Paul explains the work of Christ as Savior. As Savior, Christ gave Himself to redeem sinners.
Christ “gave himself for us” (v. 14). This short statement is loaded with meaning. First, Christ “gave” himself. Jesus said, “For even the Son of Man came not to be served but to serve, and to give his life as a ransom for many” (Mk. 10:45). That is the reason why Jesus came from heaven. He came to give his life for us. His death was a voluntary sacrifice. He was not surprised that he will undergo crucifixion. He was not forced to die on the cross. Rather, he offered himself purposely as the lamb of God on the cross.
Second, Christ gave “himself.” Christ gave his body and blood, his very life, on the cross. Note that it was Christ who gave himself, not some other person. Today, another person stands up and offers Christ as a sacrifice. But Paul wrote that Christ gave himself. Christ himself gave himself. He gave himself once for all—a one time action in the past that is good for all sins and all sinners (Heb. 9:24-10:18). All you need to do today is to trust Christ and His sacrifice.
Third, Christ gave himself “for” us. The preposition “for” (huper) can mean two things: (1) “in behalf of, for the sake of” or (2) “in place of, instead of.” (Gingrich) Christ died in behalf of us as our representative. He died instead of us as our substitute. (Marshall) In behalf us, Christ died so that we do not need to die. That is representation. Instead of us, Christ died when we should die for our sins. That is substitution. The death of Christ was a substitutionary death in behalf of and instead of every sinner.