Abū Bakr Al-Marrūdhī said:
I said to Abū ʿAbdillāh [Al-Imām Aḥmad]: ‘Whoever dies upon Islām and the Sunnah, has he died upon good?’ He said to me: ‘Be quiet! Whoever dies upon Islām and the Sunnah has died upon all good.’
Al-Waraʿ (192)
Sunnah
@Muwahhidun0

Related nuggets

Shaykh Al-Islām Ibn Taymiyyah said:
The one who refutes the people of innovation is a mujāhid, to the extent that Yahyā ibn Yahyā used to say: “Defending the Sunnah is better than jihād.”
Majmūʿ Al-Fatāwā (4/13)
Sunnah Jihad
Al-Imām Al-Awzāʿī said:
Stick firmly to the narrations of the Salaf even if people reject you. And beware of the opinions of men even if they adorn it for you with beautiful speech.
Ash-Sharīʿahʾ by Al-Ājurrī (127)
Sunnah
Abū Al-Wafāʾ Ibn ʿAqīl Al-Ḥanbalī said:
We seek refuge with Allāh from adopting a Maḏhab (position or doctrine), then seeking to validate its basis or search for its evidence.
Al-Wāḍiḥ fī Uṣūl Al-Fiqh (1/259)
Sunnah