What was the intention of the Pharisees in trying to test the Lord? It seems unlikely they anticipated any answer other than the one He provided. To explore this, we can examine that after responding to the lawyer, Jesus poses a question to the Pharisees, illustrating to them that the Messiah is not solely David's descendant, as they believed, but also the Son of God. This leads us to believe that the Pharisees recalled Jesus’ own declarations about Himself as the Son of God, which they perceived as blasphemous, since they held firmly to the belief in one God (John 10:33). They likely expected that Christ’s response to the inquiry about the most significant commandment would be one that emphasized faith and self-love (John 6:28-29), as befitting the Son of God. Had He answered in that way, the Pharisees would have branded Him a blasphemer and a violator of the law in front of the crowd.
However, Jesus first affirms the unity of God (Mark), then calls for love towards God as the foundation and essence of the entire moral law, coupled with love for one’s neighbor as an essential result of that love for God (see 1 John 4:20-21).