For those unfamiliar with this particular parable, see below.
Some years ago, I had a series of discussions with a retired pastor regarding the gospel preached by Jesus. As part of those discussions, I noticed that he would often say something like, “That can’t be what Jesus means. Corinthians says this” or “Romans says this” or what have you. So I said to him, “You know, you read Jesus’ words through the lens of Paul”. He acknowledged that he did so. In doing so, he would distort the meaning of what Jesus was saying. Sometimes completely out of proportion. It effectively rendered him incapable of understanding what Jesus was saying. So I suggested that he read the words Jesus spoke from the beginning of His ministry through the crucifixion as if the rest of the NT did not exist. To allow the words spoken by Jesus to speak for themselves. He thought about it a bit and said, “I don’t think I can do that”.
Over the years I have had similar discussions with a number of Christians with similar results. So I would make the same suggestion that I had given to the pastor. Most seemed to have no interest at all. A few actually took up the challenge. None completed it.
As such they were all like those who hear " the word of the kingdom, and do not understand it". Even worse none of them even bothered to put the effort necessary to understand it.
In my experience, most Christians do not know even the half of what Jesus taught. So they not only don’t understand the word of the kingdom, they haven’t even bothered to hear it.
While this is a relatively small sample, I have no reason to think that it isn’t representative.
Matthew 13
18“Hear then the parable of the sower. 19“When anyone hears the word of the kingdom, and does not understand it, the evil one comes and snatches away what has been sown in his heart. This is the one on whom seed was sown beside the road. 20“And the one on whom seed was sown on the rocky places, this is the man who hears the word, and immediately receives it with joy; 21yet he has no firm root in himself, but is only temporary, and when affliction or persecution arises because of the word, immediately he falls away. 22“And the one on whom seed was sown among the thorns, this is the man who hears the word, and the worry of the world, and the deceitfulness of riches choke the word, and it becomes unfruitful. 23“And the one on whom seed was sown on the good soil, this is the man who hears the word and understands it; who indeed bears fruit, and brings forth, some a hundredfold, some sixty, and some thirty.”