[1] In a lengthy Hadith...

[1] In a lengthy Hadith, Imam Sadiq -asws says: وَ أَمَّا وَجْهُ الْحَرَامِ مِنَ الْوِلَايَةِ فَوِلَايَةُ الْوَالِي الْجَائِرِ وَ وِلَايَةُ وُلَاتِهِ الرَّئِيسِ مِنْهُمْ وَ أَتْبَاعِ الْوَالِي فَمَنْ دُونَهُ مِنْ وُلَاةِ الْوُلَاةِ إِلَى أَدْنَاهُمْ بَاباً مِنْ أَبْوَابِ الْوِلَايَةِ عَلَى مَنْ هُوَ وَالٍ عَلَيْهِ وَ الْعَمَلُ لَهُمْ And as for the Prohibited aspect from the governance, it is governance of the tyrannical governor and governance of his governor, the chief from them, and followers the governor, and the one below him from the governor of the governor up to their lowest (government hierarchy) , being a door from the doors of governance upon the one, he is governing upon, and the working for them.

وَ الْكَسْبُ مَعَهُمْ بِجِهَةِ الْوِلَايَةِ لَهُمْ حَرَامٌ وَ مُحَرَّمٌ مُعَذَّبٌ مَنْ فَعَلَ ذَلِكَ عَلَى قَلِيلٍ مِنْ فِعْلِهِ أَوْ كَثِيرٍ لِأَنَّ كُلَّ شَيْ‏ءٍ مِنْ جِهَةِ الْمَعُونَةِ مَعْصِيَةٌ كَبِيرَةٌ مِنَ الْكَبَائِرِ وَ ذَلِكَ أَنَّ فِي وِلَايَةِ الْوَالِي الْجَائِرِ دُرُوسَ الْحَقِّ كُلِّهِ وَ إِحْيَاءَ الْبَاطِلِ كُلِّهِ وَ إِظْهَارَ الظُّلْمِ وَ الْجَوْرِ وَ الْفَسَادِ وَ إِبْطَالَ الْكُتُبِ وَ قَتْلَ الْأَنْبِيَاءِ وَ الْمُؤْمِنِينَ وَ هَدْمَ الْمَسَاجِدِ وَ تَبْدِيلَ سُنَّةِ اللَّهِ وَ شَرَائِعِهِ And the earning with them in aspect of the governance for them, is Prohibited , and the Prohibited is Punished, one who does that upon a little from his deed or more, because all things from aspect of the assistance is a major disobedience from the major sins , and that is because in governance of the tyrannous governor is death of the truth, all of it, and revival of the falsehood, all of it, and manifestation of the injustice and the tyranny and the corruption, and invalidation of the Books , and killing of the Prophets -as , and the Momineen, and demolishing of the Masjids, and replacement of the Sunnah of Allah -azwj and His -azwj Law.

فَلِذَلِكَ حَرَامٌ الْعَمَلُ مَعَهُمْ وَ مَعُونَتُهُمْ وَ الْكَسْبُ مَعَهُمْ إِلَّا بِجِهَةِ الضَّرُورَةِ نَظِيرِ الضَّرُورَةِ إِلَى الدَّمِ وَ الْمَيْتَةِ For those reasons, it is Prohibited to work with them , and assisting them, and earning with them, except by an aspect of necessity, being a match for the desperation to the blood and the (meat of) the dead (animals)’’ .