"Now it happened, as He went into the house of one of the rulers of the Pharisees to eat bread on the Sabbath, that they watched Him closely. And behold, there was a certain man before Him who had dropsy. And Jesus, answering, spoke to the lawyers and Pharisees, saying, 'Is it lawful to heal on the Sabbath?' But they kept silent. And He took him and healed him, and let him go. Then He answered them, saying, 'Which of you, having a donkey or an ox that has fallen into a pit, will not immediately pull him out on the Sabbath day?' And they could not answer Him regarding these things" (Luke 14:1-6).
It is likely that this Pharisee was a member of the Sanhedrin council since he is designated as "one of the rulers of the Pharisees." This is the case because the Pharisees as a group were not organized into various offices of leadership.
The fact that "they watched Him closely" may indicate Jesus was invited to this gathering for the specific purpose of being scrutinized. This would certainly be in harmony with the past behavior of the Pharisees (cf. Matt. 12:14; Luke 11:53,54; etc.). In fact, one would be surprised if they didn't specifically invite Him to try to find something against Him!
There was a certain man who was also present who had "dropsy." This is believed to have been a disease produced by the accumulation of water in various parts of the body. It was a very distressing affliction and generally incurable. His presence may or may not have been a coincidence.
Luke 14:3 states that Jesus answered them, although there is no record of Him being spoken to. Jesus is not responding to anything they have said verbally; rather, He is replying to their unspoken thoughts in which they are wondering if He would heal the sick man. If Jesus does heal the man, then they will accuse Him of violating the Sabbath law. However, if He doesn't heal the man, then they would quickly spread the news that He had failed--either to heal the man or to show mercy--or perhaps that He was afraid.
"Is it lawful to heal on the Sabbath?" This question would have caught them totally off guard for it put them in a dilemma! If they say "Yes," then they would not be able to accuse Him if He performed the healing, but if they say "No," then they would be considered unmerciful and unsympathetic by the common Jews. So, they keep silent. If they answer affirmatively or negatively, they will lose. Thus, they choose to say nothing at all. Our Lord immediately proceeded to heal the man.
Since they hadn't answered His general moral question regarding the Sabbath, Jesus proceeds to ask a question of them specifically in Luke 14:5 regarding their behavior on the Sabbath. Certainly Jesus' intention is to get these men to realize their own inconsistency and turn from it. It was hypocritical for them to pull a fallen animal out of a pit on the Sabbath and yet accuse Him (mentally on this occasion; cf. Matt. 12:11,12) of sin for miraculously relieving a suffering human on the same day. Jesus wants to know why they allow themselves freedom to practice acts of mercy on the Sabbath for animals but will not allow Him the same privilege for humans (which are much more valuable than any animal--at least in God's eyes).
"And they could not answer Him regarding these things" (Luke 14;6). They are speechless in their inconsistency! The noble thing would have been for them to admit their error and commend Jesus for His good work of mercy. But, they are too proud and hate Him too much to do that!