How do we know Jesus' sacrifice was complete?

Jesus' sacrifice is complete in that He willingly took upon Himself the sins of the elect and suffered the penalty of death intended for them. As stated in 2 Corinthians 5:21, 'For our sake He made Him to be sin who knew no sin, so that in Him we might become the righteousness of God.' This illustrates that Jesus bore our sins completely and fully fulfilled the law’s demands. Furthermore, the fact that none of His bones were broken during His crucifixion (John 19:36) serves to signify that His death was indeed the final sacrifice needed, as it perfectly satisfied the righteous requirements of God.