They say that if you are reading a sentence and you get to a word you don't understand and pass over it your reading comprehension and retention drops significantly. Things need to be defined in order to be retained.
For a long while there were words in the Bible that I didn't understand so I would just pass over them but once understood they opened great concepts up to me. Here is one example.
"For all have sinned and fall short of the glory of God, and are justified by his grace as a gift, through the redemption that is in Christ Jesus, whom God put forward as a propitiation by his blood, to be received by faith. This was to show God's righteousness, because in his divine forbearance he had passed over former sins. It was to show his righteousness at the present time, so that he might be just and the justifier of the one who has faith in Jesus. Then what becomes of our boasting? It is excluded. By what kind of law? By a law of works? No, but by the law of faith." - Romans 3:23-27 ESV
What does propitiation (Hilasterion - Strong's G2435) mean?
It is the gesture or thing that causes another person's hardness or problem with another party to go away. It appeases them or softens them again. It satisfies them. It serves as the physical reminder that there is a relationship.
In American culture it might be a gift, or flowers or a phone call. A teacher might be ready to give a low grade but the student does extra credit and hands in the missing assignments so the teacher then chooses to raise the grade.
Jesus' blood is a propitiation to God. That may sound strange to us.
"For the life of the flesh is in the blood, and I have given it for you on the altar to make atonement for your souls, for it is the blood that makes atonement by the life." - Leviticus 17:11 ESV
Spiritually speaking the 'life' of a person is in their blood. It is what is flowing and moving oxygen and food to the cells. It is what is taking away toxins and what might be harmful. But beyond that it has a spiritual dimension that we only see in part but it is there.
It is kind of how a doctor can take a blood sample and test it. When he does that the blood sample serves as a snapshot of that person's life when the blood was taken from them.
When Jesus' blood was shed it was a snapshot of His righteousness and sacrificial life as person. God sees that and is pleased with humanity again. This one person justifies everyone else who looks at that same snapshot and agrees. No one can boast anymore that what they do pleases God. A propitiation has already been made.
Jesus sent the father a bouquet of roses on our behalf large enough to fill his throne room. There is no room for any other gifts. Everything else has to sit out on the lawn.
God's hardness towards us is gone.
Thank you Jesus. Really. Thank You. The social and legal obligation has been met. God is pleased with man because of what you have done. All the prophets that have gone before rejoice when they look at what you have done. Let the ramifications of your sacrifice reach the deepest part of our hearts today. Let familiarity flee away and our own hardness be softened so that others will know what has already happened on their behalf.