Ibn Abdul Barr reported: Imam Ahmad ibn Hanbal, may Allah have mercy on him, said, “Al-Awza’i had opinions, Malik had opinions, Sufyan al-Thawri had opinions. Each of them had opinions, and it is all the same to me. Indeed, the proof is only in the narrations.”
In another narration, Imam Ahmad said, “Do not uncritically follow me, nor Malik, nor Al-Thawri, nor Al-Awza’i. Rather, take from where they took.”
Source: Jāmiʻ Bayān al-ʻIlm li-Ibn ‘Abd al-Barr 2107
عن ابن عبد البر قال أحمد بن حنبل رحمه الله رَأْيُ الأَوْزَاعِيِّ وَرَأْيُ مَالِكٍ وَرَأْيُ سُفْيَانَ كُلُّهُ رَأَيٌ وَهُوَ عِنْدِي سَوَاءٌ وَإِنَّمَا الْحُجَّةُ فِي الآثَارِ
وفي رواية أخرى قال لَا تُقَلِّدْنِي وَلَا تُقَلِّدْ مَالِكًا وَلَا الثَّوْرِيَّ وَلَا الْأَوْزَاعِيَّ وَخُذْ مِنْ حَيْثُ أَخَذُوا
2/1082 جامع بيان العلم وفضله لابن عبد البر