Today, their is a popular philosophy at the root of our culture that says biases, culture, background all shape what we can and cannot hear. In and outside the church we meet the doctrine of determinism when it comes to behavior and thought. If I do something wrong, look first at my family background, my history before judging what I have done. Jesus however seems to harp firmly on a different philosophy to Him we are responsible for believing and acting according to the truth regardless of our background and the degree we do not is sin which we should not have done and are responsible for.
A great example of this responisblity for knowing and acting is found in something Jesus said to Nicodemous.
Nicodemus said to him, “How can these things be?” Jesus answered him, “Are you the teacher of Israel and yet you do not understand these things? Truly, truly, I say to you, we speak of what we know, and bear witness to what we have seen, but you do not receive our testimony.
“but you do not receive our testimony”
To Nicodemus, a man who had come in the night to hear more from Jesus, Jesus says you do not accept my testimony or in other words we have presented everything before you that you need to receive the truth, yet you refuse to accept what we say. This accepting the testimony of Jesus is key and crucial to even taking the next step in following Him. The thing Jesus is arguing for is the common sense way in which anyone ought to look at Him and hear His words and know that this message and messagner are from God. Knowing this a person ought to listen to and obey.
In other words, Jesus is saying the one who does not purposely push Him to the side and ignore His teaching because of sin is the person who will be able to learn from Him and receive this wonderful new life. Whenever His teaching is ignored it is due to sin, this is the radical message of Jesus to the non-starter. It is not your cultural background or your group that keeps you from Jesus or that keeps His teaching from making sense. No, Jesus says it is your hard heart and your hard heart needs to get under control at this point if you wish to ever enter the Kingdom of Heaven.