The Jews knew that God had chosen them to be a nation unto Himself. They had His promises and assurance that His Son, the Messiah (Christ), the King of Israel, would be born to a virgin Jewess in a Jewish town. They knew He would rule the entire world and His people would rule with Him. Yes, they knew the good stuff of the Scriptures but they failed to comprehend God's method of achieving His ultimate plan. They failed to read Psalm 22 and Isaiah 53 and they failed to read Daniel 9:26. Oh, I am sure that they read them, but few understood them. It is funny that when Satan tempted Jesus trying to kill Him, Jesus didn't break out laughing. He knew that He would give His life freely. He could have just said, "Just be patient, Devil. I AM going to die soon enough." The same thing could have been said to the Jewish leaders who were so eager to end the "trouble-maker's" life. Instead, He let His actions teach the wisdom of God. Salvation required a blood sacrifice for the sins of the world (Galatians 1:4; 1 John 2:2), and He was prepared to offer His. Praise God!
What changed? Nothing really. God had always desired that mankind would trust in Him. God certainly didn't want anyone to perish (be lost - 1 Peter 3:9). But somewhere along the line, the Jews misunderstood. They thought that in order to please God, they had to avoid the forbidden and zealously strive to do good. What they didn't understand was that being acceptable to God was impossible on one's own merits. We know from Romans 3:10, and 3:23 that there is none righteous, no, not even one. It is God Who graciously declares those who trust in Him to be righteous in His sight. Abraham the very first Jew, believed God, and it was accounted to him for righteousness (Romans 4:3; Galatians 3:6; James 2:23). Abraham was certainly far from being righteous.
Something did change, in actuality, but it wasn't God's plan. It was the preaching of love of God seen in His grace and mercy. Grace is getting what we don't deserve - salvation. And Mercy which is not getting what we do deserve - damnation. All of a sudden, people were proclaiming "as many as" and "whosoever will" to all who would listen and trust in God's provision for salvation. Everyone had access to God. It was for any and all who would trust in Him. It was no longer understood to be a "Jewish thing," but it was available to any and all of mankind. God never changes and neither does His love for us. The Law merely pointed out that all are sinners. He loved us while we were yet sinners!
Something else changed as well. I have! God has given me the ability to believe in Him, His Word, and in His way of life. I have not arrived yet, but as my favorite verse says, "Beloved, now are we the sons of God, and it doth not yet appear what we shall; but we know that, when He shall appear, we shall be like Him, for we shall see Him as He is."(1 John 3:2) Yes, I have changed, but I long for the final change when I shall be like Him. Oh, that He would come back soon!