Nabi (sallallahu ‘alayhi wasallam) said: ‘The example of a believer who recites the Quran is like that of a citron, it has a pleasant smell and a sweet taste. And the example of a believer who does not recite the Quran is like that of a date, it has no smell, though its taste is sweet. The example of a hypocrite who recites the Quran is that of a sweet-smelling flower, it has fragrance but has a bitter taste. The example of a hypocrite who does not read the Quran is like a wild gourd, it has a bitter taste and no smell.’
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So, in the Hadith above, Nabi (sallallahu ‘alayhi wasallam) has compared abstract qualities like having Iman and reciting Quran to concrete objects which could be perceived using one’s senses. He selected specific senses of taste and related them to a person’s Iman; the things mentioned to have a sweet taste were always associated to a person having Iman whilst the things mentioned to have a bitter taste were always associated to a hypocrite.
In a similar manner, Nabi (sallallahu ‘alayhi wasallam) then selected specific senses of smell and created a correlation between them and the recitation of Quran. Thus, the objects mentioned to have a pleasant smell were associated to the recitation of the Quran and vice versa.
The commentators of Hadith have elaborated on the four parables that Nabi (sallallahu ‘alayhi wasallam) mentioned. Below are a few points that they have highlighted:
The first person described in the narration, refers to that person who has made Quran a part of his life. Along with reading it habitually, he also ensures to recite it as it ought to be recited [pondering over the meaning, implementing the lessons learned, and reciting to the best of his ability with the correct pronunciations]. Such a person has been likened to a citron, the choicest of fruit according to the Arabs.
The citron was considered the choicest of fruit according to the Arabs for a variety of reasons. Not only did it emit a most splendid fragrance, but it was also remarkably delicious, appealing to the eyes [because of its pleasant appearance and attractive color] and had many therapeutic properties. Consuming one of them would result in the cleansing of the stomach, aid in digestion, and even a pleasant fragrance in the mouth. Its benefits are numerous and have been recorded in the books of medicine
Like the citron, the Quran also purifies one’s mouth and carries with it many therapeutic qualities for the inner soul. When a believer truly makes the Quran part of his life then, like the fruit, he too becomes the choicest amongst people [This is because the Quran refines a person in every aspect, both physically and spiritually].
Hafiz Ibn Hajar (rahimahullah) has mentioned that Nabi (sallallahu ‘alayhi wa sallam) likened Iman to a sense of taste and the recitation of Quran to a sense of smell taking into consideration that the taste of an object often lasts longer than the smell. Iman is a constant in every believer’s life whereas the amount of Quran that a believer recites fluctuates time and again. Even though a certain object might lose its aroma, it won’t lose its taste [Take for example a freshly baked chocolate. Its aroma will vanish after a while, but the taste will still remain].
It is because of this that a believer who does not recite the Quran has been likened to a date. Just as a date does not emit any special fragrance, similarly a believer without the recitation of Quran has no special virtue. Nevertheless, due to the virtue of Iman deep down in a believer’s heart, he has maintained a type of sweetness no Hypocrite could ever sustain. [A date also contains within it a type of sweetness that isn’t apparent from the outside]. Ibnul ‘Arabi (rahimahullah) has mentioned that this also applies to the one who despite having memorised the Quran does not regularly engage in its recitation.
A Hypocrite who recites the Quran merely exhales puffs of aroma. This is solely due to the virtue of the Quran he is reciting. Otherwise, deep down inside he is unpleasant and bitter as he lacks the sweetness of Iman.
Therefore, he was likened to the above mentioned mentioned ‘sweet smelling’, but ‘bitter tasting’ flower.
The above is a brief exposition of the meaning of the Hadith in question.
Refer to the commentaries of Hadith for more.
(References for all of the above: Fathul Bari, Hadith: 5020, Faydul Qadir, Hadith: 8152, Mirqat: 2114; Also see: Sahih Bukhari, Hadith: 5059)
And Allah Ta’ala knows best.