john 3:10 Jesus answered and said unto him, Art thou a master of Israel, and knowest not these things? - Free Bible Online

      10. master--"teacher." The question clearly implies that the doctrine of regeneration is so far disclosed in the Old Testament that Nicodemus was culpable in being ignorant of it. Nor is it merely as something that should be experienced under the Gospel that the Old Testament holds it forth--as many distinguished critics allege, denying that there was any such thing as regeneration before Christ. For our Lord's proposition is universal, that no fallen man is or can be spiritual without a regenerating operation of the Holy Ghost, and the necessity of a spiritual obedience under whatever name, in opposition to mere mechanical services, is proclaimed throughout all the Old Testament.

JFB.