The man was a teacher. He taught the law of Moses. He was impressed when he saw Jesus answer the questions of hypocrites and doubters with wisdom:
“One of the scribes came to him, who had listened to them arguing with each other. And when he realized that he had answered them nicely, he asked him: „What is the noblest commandment before all?“ “
He felt that his opportunity had come to ask Jesus, the great teacher, which was the most important command how to be saved from entering the life and kingdom of God.

Now we have to shake off all of our preferences, everything we have been taught in Sunday schools and all the teachings of mortal people. All who love Jesus should let him speak:

“The noblest commandment,” answered Jesus, “is this: ‚Hear, O Israel, the Lord our God, is only the Lord and you shall love God your Lord with all your heart, with all your soul, with all your mind and by all your powers. ‚”

A great answer to a great question: accept that the LORD your God is one, love Him and worship Him as best you can.

But Jesus wasn’t done yet; he had more to teach. Obviously, Jesus taught the man everything he needed to enter the Kingdom of God. Jesus added:
„… The second is this: ‚You shall love your neighbor as yourself.'“

The great teacher made it clear:

„There is no other commandment greater than this.“
The man who interviewed Jesus repeated the commands to make sure that he understood them correctly:
Mark 12:32 „“ Master, you were really right, „said the man. ´He is only one and is none other than Him … ‚”
When Jesus saw that the man had learned the greatest commands correctly, he announced the good news to him:
Mark 12:34“ But when Jesus saw that he understood answered, he said to him: „You are not far from the kingdom of God.“ “

In this story of the New Testament we learn important things:

First, Jesus taught the man more than he asked, but he did not say that he was the Son of God or the Redeemer, who was sent to atone for the sins of humanity. He didn’t say anything remotely similar to what people are ordered to repeat, from ‚reborn‘ in Jesus Christ; “You have to receive me yourself, accept me as the Son of God, your personal Lord and Redeemer, who will die on the cross for your sins and will be resurrected. Allow yourself to be filled by the Holy Spirit… ”- None of this-.

Take what Jesus said and leave what people have added.

Second, salvation is dependent on this command. Jesus said this clearly when another man approached to learn from him (Mark 10: 17-29). The man fell on his knees and said to Jesus:
Mark 10: 17-18 “´Good master, what should I do that I inherit eternal life? ´ But Jesus said to him: ´What do you approve of me? Nobody is good than God alone.´ ”
Third: Jesus emphasized that there are no commands greater than these. In the event that someone might think that the greatest orders might have changed afterwards, Jesus instructed us:
Matthew 5: 17-19 “You should not believe that I have come to dissolve the law or the prophets; I did not come to dissolve, but to fulfill. Because I truly tell you: until heaven and earth go away, not the smallest letter will pass the icing on the cake until everything happens. Whoever dissolves one of these smallest commandments and teaches people that way will be called the smallest in the kingdom of heaven; but whoever does and teaches it will be called great in the kingdom of heaven.

Fourth, everyone who loves Jesus and desires eternal life must obey Jesus‘ greatest command, as he said:
John 14:15 „If you love me, you will keep my commandments.“
Matthew 19:17 „But if you want to enter life, keep the commandments.“
Fifth, a serious Christian should accept what Jesus said without twisting his words and without looking for hidden meanings. Jesus taught exactly what Moses had taught 2,000 years before him.
Deuteronomy 6: 4-5 “Listen, Israel, the Lord is our God, the Lord alone. And you shall love the LORD your God with all your heart, with all your soul, and with all your strength. ”
Jesus, may God praise him, taught the same eternal truth that ALL the prophets of God taught their people: God is one, worship Him alone.
Deuteronomy 6:13 „You shall fear the LORD your God and serve him and swear by his name.“
Deuteronomy 5: 7 “You shall have no other gods besides Me.”
Isaiah 43:11 „I, I am the LORD, and there is no Savior except Me.“
Hosea 13: 4 „But I am the LORD your God from the land of Egypt, and you should know no other God than Me and no other Savior than Me alone.“
Psalms 95: 6-7 “Come, let us worship and kneel and fall before the LORD who made us. For He is our God, and we are the people of his pasture and the sheep of his hand. If you wanted to listen to his voice today. ”
Jesus also emphasized these teachings to Satan:
Matthew 4:10 “Get away from me, Satan! For it is written: (Deuteronomy 6:13) „You shall worship God your Lord, and serve Him alone.“

Sixth, the Quran confirms Jesus‘ greatest command. The Quran teaches us that God sent all the prophets with exactly the same message: to serve the one true God alone.

“Your God is One God, there is no God but Him…” (Quran 2: 163)
“And your Lord has commanded:‘ Do not worship anyone except Him… ’(Quran 17:23)
“ And We did not send any messenger before you , to whom we have not revealed: ´There is no god but me, therefore only serve me.´ ”(Quran 21:25)
Seventh: God tells us in the Quran that on the day of judgment He will question Jesus:
“ And if God will say: “O Jesus, son of Mary, did you say to people: ‚Take me and my mother as two gods next to God?‘ …” (Quran 5: 116)

Then Jesus will answer:

“…” You are praised. I could never say what I had no right to do. If I had said it, you would surely know. You know what is in my soul, but I do not know what you have in you. You alone are the omniscient of the hidden. I said nothing to them other than what you had told me: ‚Worship God, my Lord and your Lord.‘ And I have been your witness as long as I have been among them, but after you have called me off, you are yours Been a guard; and you are the witness of all things. If you punish them, they are your servants, and if you forgive them, you are truly the Almighty, the All-Wise. ” (Quran 5: 116-118)


Source: https://www.islamland.com/deu/articles/jesus-grter-befehl