How do we know that all believers receive the same eternal reward?

The message of Matthew 20 reinforces that while believers may vary in their service to God, their ultimate reward—eternal life in Christ—is the same for all. This is illustrated in the parable, where all laborers, regardless of their working hours, receive the same coin as payment, which symbolizes God's righteousness in rewarding those He has called. It serves as a reminder that salvation and its resultant rewards are rooted in grace and not human merit, reaffirming Paul's teaching in Romans that the gift of God is eternal life through Jesus Christ.