It is reported that Imām Abū Dāwūd Al-Sijistānī – Allah have mercy on him – said:

Aḥmad b. Ḥanbal never used to involve himself in the things of this world that people involved themselves in; but when knowledge was mentioned, he would speak.

Ibn Al-Jawzī Ṣifatu Al-Ṣafwah 2:519.

It is reported that Al-Ḥusayn b. Muḥammad said:

Muḥammad b. Ismā'īl Al-Bukhārī was distinguished with three qualities – in addition to the rest of his praseworthy traits: He never spoke much, he never yearned for what people had. He would never occupy himself with other people’s affairs; all his attention was towards knowledge.

Al-Dhahabī, Siyar A’lām Al-Nubalā' 12:449