The religious scholars and the average Jewish person of Jesus time on earth thought they took “the Law”, what Moses wrote, very seriously. Jesus knew that Moses wrote about Him. He also knew they didn’t take that seriously and so discounted much of what Jesus had to say.
We read the Bible but do we always take it seriously? Jesus demands that we take the Bible and what He says seriously. It is a matter of life and death. God has a goal for us. We must take God seriously. God is God. His Word stands true for all time.
“If you won’t take seriously what Moses wrote, how can I expect you to take seriously what I speak?” ~~Jesus John 5:45-47