"They said, 'We heard a young man mentioning them'"—meaning: reviling them—"'who is called Abraham.'"
Muhammad said: "Abraham" is in the nominative case, meaning: he is called, "O Abraham," or [the one] known by it is Abraham.
﴿قَالُوا سمعنَا فَتى يذكرهم﴾ أَيْ: يَعِيبُهُمْ ﴿يُقَالُ لَهُ إِبْرَاهِيمُ﴾.
قَالَ مُحَمَّد: (إِبْرَاهِيم) رُفِعَ بِمَعْنَى يُقَالُ لَهُ: يَا إِبْرَاهِيمُ، أَوِ الْمَعْرُوفُ بِهِ إِبْرَاهِيمُ.