Jesus answered and said unto them, Ye do err, not knowing the scriptures, nor the power of God. - Matthew 22:29
The people Jesus was speaking to here, the Sadducees, were not ignorant of scripture.
They well knew of God's Word and often professed vast knowledge. In fact, in the above discourse, they tried to fool Jesus into answering a particular way when asked a question. You see, they were scholars, but not scholars of the Word. They began reading books of others' instead of the Bible until those books became their Bible.
Jesus, therefore, needed to challenge them about the book of life and the power of its writer. Jesus stated that they "do err, not knowing scripture", which is precisely what happens to us when we neglect our daily readings and study. We start imagining God does certain things when he doesn't, such as letting people into heaven simply because they are nice.
Our understanding of God wanes, until we eventually don't know Him at all, when once we did.
Today's Prayer: Dear Lord, thank you for how you challenged these people. It makes me understand that I need to maintain my scripture reading and commitment to you.