What is the most important commandment?
Jesus was asked a similar question on the following occasion:
But when the Pharisees heard that he had silenced the Sadducees, they gathered together. And one of them, a lawyer, asked him a question to test him. “Teacher, which is the great commandment in the Law?” And he said to him, “You shall love the Lord your God with all your heart and with all your soul and with all your mind. This is the great and first commandment. And a second is like it: You shall love your neighbor as yourself. On these two commandments depend all the Law and the Prophets.
Mt 22:34-40 (cf. Mk 12:28-31; Lk 10:25-28)
These two commandments, i.e. the commandment to love God and the commandment to love one’s neighbour, are the most important commandments in the Bible. There are also several summaries of the law that summarize the essentials of the law and here is a selection of these:
For you were called to freedom, brothers. Only do not use your freedom as an opportunity for the flesh, but through love serve one another. For the whole law is fulfilled in one word: “You shall love your neighbor as yourself.” But if you bite and devour one another, watch out that you are not consumed by one another.
Owe no one anything, except to love each other, for the one who loves another has fulfilled the law. For the commandments, “You shall not commit adultery, You shall not murder, You shall not steal, You shall not covet,” and any other commandment, are summed up in this word: “You shall love your neighbor as yourself.” Love does no wrong to a neighbor; therefore love is the fulfilling of the law.
So whatever you wish that others would do to you, do also to them, for this is the Law and the Prophets.
The end of the matter; all has been heard. Fear God and keep his commandments, for this is the whole duty of man. For God will bring every deed into judgment, with every secret thing, whether good or evil.
Now the end of the commandment is charity out of a pure heart, and of a good conscience, and of faith unfeigned:
He has told you, O man, what is good; and what does the Lord require of you but to do justice, and to love kindness, and to walk humbly with your God?
And now, Israel, what does the Lord your God require of you, but to fear the Lord your God, to walk in all his ways, to love him, to serve the Lord your God with all your heart and with all your soul, and to keep the commandments and statutes of the Lord, which I am commanding you today for your good?