The reason Jesus decided to die for mankind is twofold. First, as God, Jesus loved His creation! Man sinned and separated himself from God; God chose, out of His perfect love for us, to rescue us from the eternal death that our sin had caused. John 3:16 says, “For God so loved the world that He gave His only begotten Son, that whoever believes in Him should not perish but have everlasting life.”
Secondly, Jesus knew that man could not rescue Himself from eternal death. “Therefore, just as through one man sin entered the world, and death through sin, and thus death spread to all men, because all sin” (Romans 5:12). Jesus lovingly and willingly gave Himself as the perfect sacrifice to pay the penalty for sin that we could not. That sacrifice, as a payment for sin, made it possible for our debt to be justified before God the Father. Jesus’ death on the cross made the gift of salvation available to anyone who would be willing to receive it. Here are some verses that describe this miraculous act of love and justification:
John 10:17-18: “Therefore My Father loves Me, because I lay down My life that I may take it again. No one takes it from Me, but I lay it down of Myself. I have power to lay it down, and I have power to take it again. This command I have received from My Father.”
Romans 5:8, 18-19: “But God demonstrates His own love toward us, in that while we were still sinners, Christ died for us. …Therefore, as through one man's offense judgment came to all men, resulting in condemnation, even so through one Man's righteous act the free gift came to all men, resulting in justification of life. For as by one man’s disobedience many were made sinners, so also by one Man's obedience many will be made righteous.”