وَأَمَّا ذِكْرُهُ فَلِمَا مَرَّ فِي ذِكْرِ الْمُسْنَدِ إِلَيْهِ مِنْ كَوْنِهِ الْأَصْلَ
The predicate is normally mentioned because it supplies the judgment in an attribution.
زَيْدٌ عَالِمٌ
Zayd is learned.
Without «عَالِمٌ», an isolated mention of Zayd ordinarily tells us nothing about the intended judgment. The predicate is the part that communicates what is asserted, so stating it is the basic form; omission needs a recoverable clue.
But “basic” does not mean “always most eloquent.” Omission can be more suitable when a predicate is already fully understood and repetition offers no benefit. Conversely, expression is better when ellipsis would obscure the judgment.