NOTES for Mat 12:38-45
Both the scribes and the Pharisees ask Christ to perform a sign, and many among the people would, perhaps, have joined in such a request. It appears that the crowd not only knows in advance what such a sign should be, but also would like to dictate the conditions under which it is performed. Refusing to let the crowd see what it can imagine and is already prepared to interpret according to its own understanding, Christ gives another sign: His Resurrection. It will be rejected by many people, but it will still become a sign for the whole world, completely unexpected and impossible to fit into consciousness, yet grasped by faith. Signs by themselves may not lead to faith, but faith gives the ability to see the meaning of signs.
The words about what can happen after an unclean spirit is cast out apply not only to those who cast out demons "without proper qualification." Here we see a warning about the difficulties that arise on the paths of spiritual life, about its seriousness, and about the responsibility to preserve what has been received. For we risk handing the swept room over to seven more evil unclean spirits every time we voluntarily return to habitual sinful inclinations that had supposedly already been cast aside. It is hardly accidental that these words stand next to the warning about the inadmissibility of blasphemy against the Holy Spirit. Yes, the Lord is merciful. But is it possible to receive mercy while turning away from its Giver?