The Greatest Commandment from Matthew 22:37-39:
"Love the Lord your God with all your heart, and with all your soul, and with all your mind. This is the first and greatest commandment. And the second is like it: 'Love your neighbor as yourself.' All the Law and the Prophets hang on these two commandments."

The Great Commission from Matthew 28:19,20
...Go and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, and teaching them to obey everything I have commanded you. And surely I am with you always, to the very end of the age."