Whenever a lawyer (an expert in the Old Testament Law) asked Jesus what the greatest commandment was, he was essentially asking Him, “What’s the one thing I can do for God so I can forget about the rest?”
Jesus said, “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 foremost commandment. The second is like it, ‘You shall love your neighbor as yourself.’ On these two commandments depend the whole Law and the Prophets.”
You want the “one thing”? Love God with everything you have. But He didn’t just leave it there, He said to love your neighbor (anyone else on the planet) as yourself (you naturally take care of your own basic physical needs, protect yourself from harm, etc.). Jesus not only answered their question, but answered the underlying question by basically saying, “the entire Bible as you know it is based off of these two commandments.”
The Bible is not a list of do’s and don’ts, it a love letter from God that shows us how to find His love and how to share that love with others.
Galatians 5:14 (NASB)
For the whole Law is fulfilled in one word, in the statement, “You shall love your neighbor as yourself.”
Matthew 22:35–40; Luke 10:36–37; Romans 13:8–10; James 2:8; 1 Corinthians 10:24