The predicate may be a prepositional phrase. In these examples, the indefinite noun after لَا is still the noun of لَا, while the following phrase completes the meaning as its predicate.
Sentence
اسمُ لَا
Predicate phrase
Meaning
لَا إِكْرَاهَ فِي الدِّينِ
إِكْرَاهَ
فِي الدِّينِ
There is no compulsion in religion
لَا مِلْحَ فِي هَذَا الطَّعَامِ
مِلْحَ
فِي هَذَا الطَّعَامِ
There is no salt in this food
لَا رَيْبَ فِيهِ
رَيْبَ
فِيهِ
There is no doubt in it
لَا تَثْرِيبَ عَلَيْكُمُ الْيَوْمَ
تَثْرِيبَ
عَلَيْكُمُ
There is no blame on you today