Hadith 1:

مُحَمَّدُ بْنُ يَحْيَى عَنْ مُحَمَّدِ بْنِ الْحُسَيْنِ عَنْ صَفْوَانَ بْنِ يَحْيَى عَنِ الْعَلاءِ بْنِ رَزِينٍ عَنْ مُحَمَّدِ بْنِ مُسْلِمٍ قَالَ سَمِعْتُ أَبَا جَعْفَرٍ  يَقُولُ كُلُّ مَنْ دَانَ الله بِعِبَادَةٍ يُجْهِدُ فِيهَا نَفْسَهُ وَلا إِمَامَ لَهُ مِنَ الله فَسَعْيُهُ غَيْرُ مَقْبُولٍ وَهُوَ ضَالٌّ مُتَحَيِّرٌ وَالله شَانِئٌ لاعْمَالِهِ وَمَثَلُهُ كَمَثَلِ شَاةٍ ضَلَّتْ عَنْ رَاعِيهَا وَقَطِيعِهَا فَهَجَمَتْ ذَاهِبَةً وَجَائِيَةً يَوْمَهَا فَلَمَّا جَنَّهَا اللَّيْلُ بَصُرَتْ بِقَطِيعٍ مَعَ غَيْرِ رَاعِيهَا فَحَنَّتْ إِلَيْهَا وَاغْتَرَّتْ بِهَا فَبَاتَتْ مَعَهَا فِي رَبَضَتِهَا فَلَمَّا أَنْ سَاقَ الرَّاعِي قَطِيعَهُ أَنْكَرَتْ رَاعِيَهَا وَقَطِيعَهَا فَهَجَمَتْ مُتَحَيِّرَةً تَطْلُبُ رَاعِيَهَا وَقَطِيعَهَا فَبَصُرَتْ بِغَنَمٍ مَعَ رَاعِيهَا فَحَنَّتْ إِلَيْهَا وَاغْتَرَّتْ بِهَا فَصَاحَ بِهَا الرَّاعِي الْحَقِي بِرَاعِيكِ وَقَطِيعِكِ فَإِنَّكِ تَائِهَةٌ مُتَحَيِّرَةٌ عَنْ رَاعِيكِ وَقَطِيعِكِ فَهَجَمَتْ ذَعِرَةً مُتَحَيِّرَةً نَادَّةً لا رَاعِيَ لَهَا يُرْشِدُهَا إِلَى مَرْعَاهَا أَوْ يَرُدُّهَا فَبَيْنَا هِيَ كَذَلِكَ إِذَا اغْتَنَمَ الذِّئْبُ ضَيْعَتَهَا فَأَكَلَهَا وَكَذَلِكَ وَالله يَا مُحَمَّدُ مَنْ أَصْبَحَ مِنْ هَذِهِ الامَّةِ لا إِمَامَ لَهُ مِنَ الله جَلَّ وَعَزَّ ظَاهِراً عَادِلاً أَصْبَحَ ضَالاً تَائِهاً وَإِنْ مَاتَ عَلَى هَذِهِ الْحَالِ مَاتَ مِيتَةَ كُفْرٍ وَنِفَاقٍ وَاعْلَمْ يَا مُحَمَّدُ إِنَّ أَئِمَّةَ الْجَوْرِ وَأَتْبَاعَهُمْ لَمَعْزُولُونَ عَنْ دِينِ الله قَدْ ضَلُّوا وَأَضَلُّوا فَأَعْمَالُهُمُ الَّتِي يَعْمَلُونَهَا كَرَمَادٍ اشْتَدَّتْ بِهِ الرِّيحُ فِي يَوْمٍ عَاصِفٍ لا يَقْدِرُونَ مِمَّا كَسَبُوا عَلَى شَيْ‏ءٍ ذَلِكَ هُوَ الضَّلالُ الْبَعِيدُ 

Narrated with a chain of trustworthy narrators that Abu Jafar Imam Baqir (عليه السلام) said,

"Whoever worships Allah with acts of worship in which he exerts himself, but does not have an Imam appointed by God, then his effort is not accepted, and he is lost and confused. And Allah dislikes his deeds.

His situation is like that of a sheep that has strayed from its shepherd and its flock. It wanders aimlessly, day and night. When night falls, it sees another flock without its shepherd and yearns for it, so it stays with it in the night. When the shepherd drives his flock, the sheep denies the shepherd and flock and wanders confusedly, seeking its own shepherd and flock. It sees another flock with its shepherd and yearns for it, but the shepherd calls out to it, "Go and join your own shepherd and your own flock, you are lost and confused about your shepherd and flock."

So the sheep wanders fearfully and confusedly, crying out with no shepherd to guide it to its pasture or take it back to the shelter. And while it is in this state, a wolf seizes and kills & eats it.

Similarly, by Allah, O Muhammad (the narrator), whoever from this nation does not have an well-known and Just Imam appointed by Allah (جل وعز), becomes lost and goes astray. And if he dies in this state, he dies the death of an unbeliever and hypocrite.

And Know, O Muhammad (the narrator), that the unjust Imams and their followers are cut off from the religion of Allah. They have gone astray and led others astray. Their deeds are like ashes scattered by a strong wind on a stormy day. They cannot retain anything from what they have earned. This is the ultimate deviation."

[Source: al-Kafi, Vol. 1, Pg. 374, Hadith. 2]

Hadith 2:

أَبِي ره قَالَ حَدَّثَنِي مُحَمَّدُ بْنُ يَحْيَى الْعَطَّارُ عَنْ مُحَمَّدِ بْنِ أَحْمَدَ قَالَ حَدَّثَنِي إِبْرَاهِيمُ بْنُ إِسْحَاقَ عَنْ مُحَمَّدِ بْنِ سُلَيْمَانَ الدَّيْلَمِيِّ عَنْ أَبِيهِ عَنْ قَيْسٍ بَيَّاعِ الزُّطِّيِّ قَالَ: دَخَلْتُ عَلَى أَبِي عَبْدِ اللَّهِ ع فَقُلْتُ لَهُ جُعِلْتُ فِدَاكَ إِنَّ لِي جَاراً لَسْتُ أَنْتَبِهُ إِلَّا عَلَى صَوْتِهِ إِمَّا تَالِياً كِتَاباً يَخْتِمُهُ أَوْ يُسَبِّحُ لِلَّهِ عَزَّ وَ جَلَّ قَالَ إِلَّا أَنْ يَكُونَ نَاصِبِيّاً فَسَأَلْتُ عَنْهُ فِي السِّرِّ وَ الْعَلَانِيَةِ فَقِيلَ لِي إِنَّهُ مُجْتَمِعُ الْمَحَارِمِ قَالَ فَقَالَ يَا مَيْسَرَةُ يَعْرِفُ شَيْئاً مِمَّا أَنْتَ عَلَيْهِ قُلْتُ اللَّهُ أَعْلَمُ فَحَجَجْتُ مِنْ قَابِلٍ فَسَأَلْتُ عَنِ الرَّجُلِ فَوَجَدْتُهُ لَا يَعْرِفُ شَيْئاً مِنْ هَذَا الْأَمْرِ فَدَخَلْتُ عَلَى أَبِي عَبْدِ اللَّهِ ع فَأَخْبَرْتُهُ بِخَبَرِ الرَّجُلِ فَقَالَ لِي مِثْلَ مَا قَالَ فِي الْعَامِ الْمَاضِي يَعْرِفُ شَيْئاً مِمَّا أَنْتَ عَلَيْهِ قُلْتُ لَا قَالَ يَا مَيْسَرَةُ أَيُّ الْبِقَاعِ أَعْظَمُ حُرْمَةً قَالَ قُلْتُ اللَّهُ وَ رَسُولُهُ وَ ابْنُ رَسُولِهِ أَعْلَمُ قَالَ يَا مَيْسَرَةُ مَا بَيْنَ الرُّكْنِ وَ الْمَقَامِ رَوْضَةٌ مِنْ رِيَاضِ الْجَنَّةِ وَ اللَّهِ لَوْ أَنَّ عَبْداً عَمَّرَهُ اللَّهُ فِيمَا بَيْنَ الرُّكْنِ وَ الْمَقَامِ أَلْفَ عَامٍ وَ فِيمَا بَيْنَ الْقَبْرِ وَ الْمِنْبَرِ يَعْبُدُهُ أَلْفَ عَامٍ ثُمَّ ذُبِحَ عَلَى فِرَاشِهِ مَظْلُوماً كَمَا يُذْبَحُ الْكَبْشُ الْأَمْلَحُ ثُمَّ لَقِيَ اللَّهَ عَزَّ وَ جَلَّ بِغَيْرِ وَلَايَتِنَا لَكَانَ حَقِيقاً عَلَى اللَّهِ عَزَّ وَ جَلَّ أَنْ يُكِبَّهُ عَلَى مَنْخِرَيْهِ فِي نَارِ جَهَنَّمَ

The narrator says,

I entered upon Abu Abd-Allah Imam Sadiq (عليه السلام), and I said to him, "May I be sacrificed for You. I have a neighbor whom I do not notice except by his voice, either reciting the book (Quran) that he completes or glorifying Allah (عز وجل).

The Imam (عليه السلام) said, "Unless he is a Nasibi (i.e. the one who hates the Imams)." 

So I (the narrator) asked about him secretly and openly, and it was said to me that he stays away from all forbidden things. 

Then the Imam (عليه السلام) said, "O Maysara, does he know anything of what you are upon (i.e. Wilayat)?" 

I (the narrator) said, "Allah knows best."

So I performed Hajj the following year and inquired about the man, and I found that he did not know anything of this matter (i.e. did not believe in Mastership/Wilayat of the Imams). 

So I entered upon Imam Sadiq (عليه السلام), and I informed him of the man. 

So the Imam said to me as he had said the previous year, "Does he know anything of what you are upon?" 

I (the narrator) said, "No." 

The Imam then said, "O Maysara, which place is the most honorable?" 

I (the narrator) said, "Allah and His Messenger and the son of His Messenger know best." 

The Imam said, "O Maysara, that which is between the Rukn (black stone in the Kaaba) and the Maqam (the place of the foot prints of Prophet Ibrahim ع) is a garden from the gardens of Paradise, and by Allah, if a servant were to live a thousand years between the Rukn and the Maqam and worship Allah for a thousand years between the Prophets grave and the Pulpit (minbar), then was slaughtered on his bed being oppressed (mazloom) as a sheep is slaughtered, and then meets Allah (عز وجل) without Our Mastership (Wilayah), then it would be rightful for Allah (عز وجل) to throw him on his face into the Fire of Hell."

[Source: Iqab al-Amal, Shaikh Sadooq, Chapter. 9, Hadith. 16]

Hadith 3:

 عنه، عن أبي يوسف يعقوب بن يزيد، عن المبارك، عن عبد الله بن جبلة، عن حميدة، عن جابر، عن أبي جعفر عليه السلام قال: قال رسول الله صلى الله عليه وآله التاركون ولاية علي، المنكرون لفضله، المظاهرون أعداءه، خارجون من الاسلام من مات منهم على ذلك

Narrated from Aba Jafar Imam Mohammad Baqir (عليه السلام), that the Prophet (صلى الله عليه وآله) said,

"Those who leave the Wilayah of Imam Ali (عليه السلام), those who deny His mertis, those who support His enemies, are out of the fold of Islam, if they die upon it."

[Source: al-Mahasin, Vol. 1, Pg. 186]

Hadith 4:

حدثنا محمد بن علي، عن أبيه، عن علي بن إبراهيم بن هاشم، عن أبيه، عن ابن أبي عمير، عن أبان الأحمر قال: قال الصادق عليه السلام: يا أبان كيف ينكر الناس قول أمير المؤمنين عليه السلام لما قال: " لو شئت لرفعت رجلي هذه فضربت بها صدر ابن أبي سفيان بالشام فنكسته عن سريره " ولا ينكرون تناول آصف وصي سليمان عرش بلقيس وإتيانه سليمان به قبل أن يرتد إليه طرفه، أليس نبينا صلى الله عليه وآله أفضل الأنبياء ووصيه عليه السلام أفضل الأوصياء، أفلا جعلوه كوصي سليمان، حكم الله بيننا وبين من جحد حقنا وأنكر فضلنا

Narrated that Imam Sadiq (عليه السلام) said,

"O Aban, how do people deny the saying of Amir al-Momineen (عليه السلام) when He said, 'If I had wished, I would have raised this foot of mine and with it struck the chest of Ibn Abi Sufyan (i.e. Muawiyah) in Syria and overturned him from his bed?' 

And they do not deny that Asif, the guardian (wasi) of Prophet Sulayman (ع), brought the throne of Bilqis and placed it before Solomon before his eye blinked. 

Is not our Prophet (i.e. Muhammad ص) the best of the Prophets and His guardian (i.e. Imam Ali ع) the best of the guardians? Have the people not considered Imam Ali (ع) even like the guardian of Sulayman? May Allah has judge between Us and those who denied Our right and denied our Merits (Fadhl)."

[Source: al-Ikhtesas, Shaikh Mufeed, Pg. 212-213]

Hadith 5:

حدثني ابي عن النضر بن سويد عن يحيى الحلبي عن ابي حمزة الثمالي عن ابي جعفر عليه السلام قال يبعث الله يوم القيامة قوما بين أيديهم نور كالقباطي ثم يقال له كن هباء‌ا منثورا ثم قال: أما والله يا ابا حمزة انهم كانوا ليصومون ويصلون ولكن كانوا إذا عرض لهم شئ من الحرام اخذوه وإذا عرض لهم شئ من فضل امير المؤمنين عليه السلام انكروه

Narrated that Abu Jafar Imam Baqir (عليه السلام) said, 

"On the day of Judgement, Allah (عز وجل) will raise a community, in front of them will be a light like al-Qabati (a white cloth). Then it will be said to it, "Become scattered dust". 

Then the Imam (عليه السلام) said, "By Allah (عز وجل)! O Aba Hamza, These people used to fast & pray but when anything forbidden was presented to them they would take it. And when any thing from the merits (fadail) of Amir al-Momineen (عليه السلام) is presented to them they would deny it."

[Source: Tafseer al-Qummi, Vol.2 Pg.113]