In Matthew 8:31 we read that Jesus heard the pleas of the demons. Why should he do so?

This is a really thought-provoking question!

The verse in question refers to when Jesus heals the Gerasene (or Gadarene) demoniacs, and the demons plead to be sent into the swine.

The first thing to know is that Jesus is absolutely sovereign. He acts on divine authority, an authority so absolute that even the demons are subject to his command. With just a single command, the seemingly-powerful demons are driven out of the demoniacs into the swine.

So since Jesus has absolute authority in this situation, the demons would not even be capable of pleading with Jesus unless he permitted it.

But why would he permit it…? It’s not for the sake of the demons; it’s for the sake of us.

In other words, Jesus didn’t permit the demons to plead being sent into the swine because he had compassion on their evil intentions. Rather, he allowed them to speak so that those witnessing the exorcism could see that Jesus had the authority to make the demons do whatever he commanded. Everyone was terrified of the demoniac and this supposedly great power of those evil spirits–but as soon as Jesus speaks his command, the demons are powerless and are left groveling and begging. As the Son of God and the Messiah, Jesus’ power and authority over all creation is absolute!Notice also that Jesus used everything in that situation to bring greater glory to the Father: when Jesus permits the demons to enter the herd of swine, the entire region comes to know about the miracle Jesus performed!