What is the ruling on insulting the Companions before their conversion to Islam, and is there a repentance for it?

It is not clear what is meant by reviling the Companions before their conversion to Islam. However, if the intention is to revile them for actions they committed before their conversion, then this is not permissible, because Allah forgave them for that through their conversion to Islam, as confirmed by His saying, "Say to those who disbelieve, if they cease, what has passed will be forgiven them." And as the Prophet, peace and blessings be upon him, said to Amr ibn al-Aas, "Did you not know that Islam demolishes what was before it?" If Allah has forgiven them, then it is not permissible to revile them, and whoever has reviled them must repent to Allah.