How can Old Testament believers be saved by believing in Jesus?

How were Old Testament people saved. What did they understand about Christ and His sacrifice?

Statements like John 3:36, 14:6, Acts 4:12 and I Timothy 2:5 allow us to infer from Scripture that it is impossible to be saved apart from the work of Christ and personal faith in Him. That inference is justified by the clear teaching of Romans 3:25,26. The statement "the remission of sins that are past through the forbearance of God" is linked with the propitiatory death of our Lord Jesus. He was the foreordained Lamb. His death was a certainty in the purposes of God and enabled God, in His forbearance, to forgive sin in light of a coming Calvary (Psalm 32:1). It is wonderful to think of the Spirit of God gently dealing with a devout Hebrew who was searching for God and wondering what the significance of the many sacrifices was. I Peter 1:10,11 refers to those who searched diligently for the meaning and time of the fulfillment of prophecies relating to salvation. Imagine Daniel's awe when it was revealed to him that Messiah would be "cut off!" Many of those Old Testament believers could join us in singing, "O wondrous hour when God to me, a vision gave of Calvary."

E. Higgins