And behold, a lawyer (an expert in religious law) stood up to put Him to the test, saying, “Teacher, what shall I do to inherit eternal life?” And Jesus replied, “What is written in the Law? How do you read it?” And the lawyer answered, “You shall love the Lord your God with all your heart and with all your soul and with all your strength and with all your mind, and your neighbor as yourself.” And Jesus said to him, “You have answered correctly. Do this, and you will live.” Luke 10:25-28 (Note 1)

This explication of ‘what is written in the Law’ (Note 2) by the expert in religious law, combines Deuteronomy 6:5 (“heart, soul, and might”) and the command from Leviticus 19:18 (“love your neighbor as yourself”). In the Gospels, Jesus describes these as the greatest and second-greatest commandments (Matthew 22:37-39).

Note 1: Also Mark 12:29-31, and Matthew 22:37-39.
Note 2: “The Law” is the Torah, the first five books of The Old Testament (Genesis, Exodus, Leviticus, Numbers, and Deuteronomy).