Layth reported: Tawus, may Allah have mercy on him, if the people became too strict in a matter, he would grant them a concessions in it. If the people became too permissive in a matter, he would make them be more strict in it. Layth said, “That is truly knowledge.”
Source: Tārīkh Ibn Abī Khaythamah 1100
عَنْ ليث قال كان طاووس رحمه الله إذا تشدَّدَ الناس فِي شيءٍ رخَّصَ فيه وإذا ترخص الناس فِي شيء تشدد فيه قَالَ ليث وذلك العِلم
1100 تاريخ ابن أبي خيثمة