In religious terminology...
In religious terminology, Shafa’a means “a creature’s mediation between God and another creature in delivering the good or driving away the evil whether in this world or the Hereafter.” Shafa’a means to make a change in the sinner so that the sinner no longer deserves to be punished and exclude one from the law of punishment; like repentance makes a wrongdoer no longer deserve the punishment and makes one deserve receiving God’s forgiveness, as Imam ‘Ali (PBUH) has said in one of his speeches: “There is no Shafi’ (intercessor) more rescuing than repentance.” (Al-Majlisi, Bihār al-Anwār, vol.6 p.19) NOTE: False Intercession False intercession is when the wrongdoer acts against the law and influences the will of the lawmaker through an illegal way.
Such kind of intercession in this world is an act of oppression and it is impossible in the hereafter. (Mutahhari, ‘Adl-i ilahi, p. 234) The objections to intercession are mostly of this kind and this is rejected in the Qur’an as well.
The false intercession originates from the belief in Tafwid (unrestricted human delegation) which is a wrong belief meaning that after creating the world, God delegated its management to others and He has no role in it and thus people would be able to make intercession independently and if one can attract the intercessors’ favour, he would not need God.
True Intercession True intercession as mentioned in the Qur’an which is believed by Shi’a and supported by Imams (peace be upon them) is that intercession in its wholeness belongs to God and no one can make intercession without His permission. Prophets and Imams’ intercession never means that they have an independent role or that to be privileged by their intercession, one would need to do anything other than what God has ordered.
On the contrary, they would only make intercession for someone, whom God would be pleased with. “…and they do not intercede except for someone He approves of …” (Qur’an 21:28) Types of Intercession Intercession can be divided into two types: 1. Generative Intercession Generative (Takwinī) intercession refers to intercession in the literal sense with its endless occurrences. There are boundless instances of generative intercession in the world.
All the causes intercede for their effects in order to come into existence. There is a tendency for stronger beings to help the weak.