AHAADEETH ON UNITY

Ahaadeeth are from "Tarteeb Saheeh-ul-Jaami'":
 

1) Verily Allah ordered Yahyaa ibn Zakariyyaa with five words - that he should act on them and order the Children of Israel to act on them... ... And I order you with five 
which Allah ordered me:

a) Jama'ah (i.e the Sunnah and its people),

b) and hearing,

c) and obeying,

d) and Hijrah,

e) and Jihad in the way of Allah,

As he who goes away from the Jama'ah by a hands span, then he has thrown off the yoke of Islam from his neck unless he returns; and he who calls to the call of Jahiliyyah, then he is of the heap of the Hell-Fire even if he fasts, prays and declares that he is a Muslim. So call with the call of Allah by which He called you Muslims, believers, worshippers of Allah.[Saheeh: Reported by Ahmad, at-Tirmidhee, an-Nasaa`ee & others from al-Haarith ibn al-Haarith al-Ash'aree (radhiAllaahu 'anhu)]
 

2) Allah will not unite my Ummah upon misguidance, and Allah's Hand is upon the Jama'ah... [Saheeh: Reported by at-Tirmidhee from Ibn 'Umar (radhiAllaahu 'anhumaa)]
 

3) Verily your being divided in the mountain passes and valleys is from Shaytaan. [Saheeh: Reported by Ahmad, Abu Dawud & al-Haakim from Abu Tha'labah al-Khushanee (radhiAllaahu 'anhu)]
 

4) I advise for you my companions, then those who come after them. Then lying will become widespread to such an extent that oaths will be sworn (upon falsehood) without its being sought and witness will be given (falsely) without it being asked for. Verily no man is alone with a woman (i.e non-mahram) in private except Shaytaan is the third of them. Stick to the Jama'ah and beware of disunity. For indeed Shaytaan is with the single (person) and he is further away from two (people). He who desires the centre of Paradise, then let him stick to the Jama'ah. He whose good deed pleases him and whose bad deed grieves him, then he is the believer. [Saheeh: Reported by Ahmad, at-Tirmidhee & al-Haakim from 'Umar (radhiAllaahu 'anhu)]
 

5) Beware! Those who were before you from the People of the Book split into seventy-two sects and verily this community will split into seventy three: Seventy-two in the Fire and one in Paradise, and it is the Jama'ah. And there will appear amongst my Ummah people through whom desires flow just as rabies flows through the patient not leaving any vein or joint except that it penetrates it. [Saheeh: Abu Dawud from Mu'aawiyah (radhiAllaahu 'anhu)]
 

6) The Jama'ah is a mercy and discord is punishment. [Hasan: 'Abdullaah ibn Ahmad in "al-Musnad"  & al-Qudaa'ree from an-Nu'maan ibn Basheer (radhiAllaahu 'anhu)]
 

7) There will be after me calamity upon calamity and so he whom you see leave the Jama'ah or wishes to cause separation in the matter of the Ummah of Muhammad - then kill him whoever he is, for certainly Allah's Hand is with the Jama'ah, and certainly Shaytaan is with the one who leaves the Jama'ah, urging him on. [Saheeh: An-Nasaa`ee & Ibn Hibbaan from 'Arfajah (radhiAllaahu 'anhu)] 

8) Why do I see you (plural) sitting separately (in groups)? [Saheeh: Ahmad, Muslim, Abu Dawud & an-Nasaa`ee from Jaabir ibn Samurah (radhiAllaahu 'anhu)]

9) Do not differ, for those who were before you differed and were destroyed. [Saheeh: Al-Bukhaaree from Ibn Mas'ood (radhiAllaahu 'anhumaa)]

10) Ibn  mas'ood (RadhiAllaahu 'anhu) said "The jamaa'ah is what conforms to the truth, even if you are alone" [Reported by ibn Asaakir in Taareek Dimashq with Saheeh isnaad as pointed out by Shaikh Al-Albaanee in al-Mishkaar (1/61)]