What does a merciful justice mean? Does suffering have a meaning? What is its relationship with repentance? What type of cosmological and theological effects can this repentance have?
In Isa 30:18-26 we have an emphasis on the faithfulness of YHWH based on his merciful justice. This merciful justice cannot be frustrated by human infidelity. God's grace is manifested in blessing the rebellious children. The time of suffering will be over and the time of repentance will come. That is when the people will do away with all the evil ways of behaving, will get rid of the idols and heed to the voice of YHWH. Then the earth will also rejoice and participate in the blessings that people will enjoy. There will be abundant rain and fertility. The oppressing enemies will give way to prosperity. This is the Lord's healing promise.
In other words, we admit that the biblical passage presents five themes: a) God's merciful justice; b) The aim of suffering; c) Human response; d) Cosmological effects; e) God's healing.