The Pope said that the doctors of the law did not understand what Jesus meant because they did not understand the joy of hope, of promise and of the covenant.
"They did not know how to rejoice, because they lost the meaning of joy that only comes from faith," he said. "Our father Abraham was able to rejoice because he had faith: he was made just in faith. These lost their faith. They were doctors of the law, but without faith! But more so: they lost the law! Because the center of the law is love, love for God and for neighbor."
The Holy Father went on to say that the doctors of the law were so attached to doctrine that their often times their questions dealt in abstract circumstances.
"Should taxes be paid to Cesar, or should they not? This woman, who was married seven times, when she goes to Heaven will she be the wife of those seven? […] This was their world, an abstract world, a world without love, a world without faith, a world without hope, a world without trust, a world without God," he noted. "And this is why they could not rejoice!"
The 78 year old Pontiff continued saying that it was sad to be a believer without joy. Without joy, he said, there is no faith, only "cold doctrine."
Concluding his homily, Pope Francis said that the joy of faith and the Gospel is the touchstone of one's faith. Without it, one is not a "true believer."
"We return home, but first we make this celebration here with these words of Jesus: ' Abraham your father rejoiced to see my day; he saw it and was glad.' And ask the Lord for the grace to be joyful in hope, the grace to be able to see Jesus' day when we find ourselves with Him and the grace of joy," he concluded.