"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." (Matthew 22:37-38)
A king prepares a wedding banquet for his son and sends invitations. Those invited refuse to come. He sends more servants: they ignore the invitation and some seize and kill the messengers. The king destroys them and sends servants to the street corners to invite anyone they find. The hall is filled with guests. But when the king comes in he finds a man without a wedding garment. He is thrown out into the darkness. The parable is dense with theology: the original invitees are Israel's religious establishment. The street-corner guests are the Gentiles and the outcasts. But acceptance of the invitation does not remove the requirement of the wedding garment, the righteousness that God provides and that the guest must put on. Baptism gives the garment; the Christian life is the wearing of it. St. Augustine identified the wedding garment with charity: what makes a person fit for the Kingdom is not the accident of having been invited but the transformation of the soul by love.
Three groups come in succession to trap Jesus. The Pharisees and Herodians ask about taxes to Caesar. The Sadducees pose a resurrection riddle. The Pharisees send a lawyer to ask which commandment is greatest. To each Jesus gives an answer that silences them. The greatest commandment: love God with all your heart, soul, and mind. The second: love your neighbour as yourself. All the Law and the Prophets hang on these two commandments. The entire revealed will of God is the elaboration of these two loves. Then Jesus poses a question no one can answer: if the Christ is the Son of David, why does David in Psalm 110 call him Lord? The Christ is simultaneously David's son in his humanity and David's Lord in his divinity. He who answers all their questions is himself the unanswerable question that stands over all human wisdom.
Brothers and sisters, the Pharisees asked which commandment is greatest and received the answer that contains all answers. Love God. Love neighbour. The whole moral life flows from these two. If you are ever uncertain about what to do, begin here: which option most fully expresses love of God and love of neighbour? Start there and the Law and the Prophets will follow.
Lord Jesus, you named love as the greatest commandment and the fulfilment of all the law. Pour your love into our hearts by the Holy Spirit so that we may love the Father with everything we are and our neighbour with the same regard we have for ourselves. Make us wedding guests who wear the garment of your righteousness. Through Christ our Lord. Amen.