Ibn Taahir al-Maqdisi al-Haafidh said, "I heard the Imaam, Abu Ismaa'eel 'Abdullaah bin Muhammad al-Ansaari saying, whilst in Haraah: 'The sword was put to my neck five times [and each time] it was not said to me, 'Leave your madhhab' but it was said to me, 'Remain silent about those who are in opposition to you'. So I would say, 'I will not remain silent'." [Aadaab us-Sharee'ah (1/207) of Ibn Muflih al-Maqdisi al-Hanbali].

Al-Humaidee, the Shaikh of al-Bukhaaree said, "By Allaah, that I war against those who reject the Hadeeth of the Messenger (sallallaahu alaihi wasallam) is more beloved to me than that I should war against the same number of Non-Muslims." [Al-Harawi in Dhamm ul-Kalaam].

Ibn al-Qayyim said, "The jihaad with decisive proofs [from the Book and the Sunnah] and the tongue takes precedence over the jihaad with the sword and the spear." [Al-Jawaab us-Saheeh of Ibn Taymiyyah (1/237)].

Nasr bin Zakariyaa said, I heard Muhammad bin Yahyaa adh-Dhuhlee saying, I heard Yahyaa bin Yahyaa saying, "Defence of the Sunnah is more superior than Jihaad in the path of Allaah." So I said, "A man spends his wealth, tires his body and strives (in jihaad), so is this one (still) better than him? He said, "Yes, by many times!" [Dhammu ul-Kalaam of al-Harawi].

Source

We should reject division and deviation and cling to the Qur'an and the Sunnah.

30:31-32. (Always) Turning in repentance to Him (only), and be afraid and dutiful to Him; and perform As Salât (Iqâmat as Salât) and be not of Al*Mushrikûn (the disbelievers in the Oneness of Allah, polytheists, idolaters, etc.).

Of those who split up their religion (i.e. who left the true Islâmic Monotheism), and became sects, [i.e. they invented new things in the religion (Bid'ah), and followed their vain desires], each sect rejoicing in that which is with it.