Once Luqman’s master said to him: “Slaughter this sheep for us and bring the best two pieces from it”, so he brought out the tongue and the heart.
After few days, his master said: “Slaughter this sheep for and bring the worst two morsels from it”, so he brought out the tongue and the heart.
His master said to him, “I told you to bring out the best two pieces, and you brought these, then I told you to bring out the worst two pieces, and you brought these!”
Luqman Hakeem said “There is nothing better than these if they are good, and there is nothing worse than these if they are bad.”
Source: Tafsir Ibn Kathir, 5/499