Short Answer

There does not seem to be a Hadith saying that whoever does not make a lot of Dhikr has no Iman. Rather it seems the person narrating this has confused it with a narration from Tabarani, which is considered a fabrication. So, this person seems to be such a problematic narrator that he misquoted a narration that is a fabrication. He did not know about the fabrication, and he did not know he is misquoting it.

Explanation

عَنْ أَبِي هُرَيْرَةَ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ: مَنْ أَكْثَرَ ذِكْرَ اللَّهِ فَقَدْ بَرِئَ مِنَ النِّفَاقِ. لَمْ يَرْوِهِ عَنْ سُهَيْلٍ إِلَّا حَمَّادٌ تَفَرَّدَ بِهِ مُؤَمَّلٌ

Abu Hurairah narrated that The Messenger of Allah ﷺ said: Whoever is abundant in the remembrance of Allah has been absolved of hypocrisy. No one narrated it from Suhayl except Hammad. And Muammal was the only one to narrate it. (Tabarani al-Mujam al-Sagheer, 974).

The narration above encourages being abundant in Dhikr. And it mentions one of its virtues. It does not say that someone who is not abundant in Dhikr has no Iman. Therefore, the person who narrated, ‘Whoever does not make a lot of Dhikr has no Iman,’ is an extremely problematic narrator.

That is because he is narrating something fabricated to begin with. But then he misquotes the fabrication. We assume that he did not fabricate the Hadith himself. Rather he was ignorant regarding it. And his lack of knowledge regarding Hadith science caused him to misquote the fabrication too.

Imams of Hadith

As we see from the above discussion, the narration saying whoever does not make a lot of Dhikr has no Iman is a misquote of another Hadith narration. That other Hadith was considered fabricated by the Imams of Hadith. In the following Nass, Imam al-Haythami specified the fabricator. Namely, Muammal bin Ismail.

رَوَاهُ الطَّبَرَانِيُّ فِي الصَّغِيرِ وَالْأَوْسَطِ عَنْ شَيْخِهِ: مُحَمَّدِ بْنِ سَهْلٍ الْمُهَاجِرِ، عَنْ مُؤَمَّلِ بْنِ إِسْمَاعِيلَ وَفِي الْمِيزَانِ: مُحَمَّدِ بْنِ سَهْلٍ، عَنْ مُؤَمَّلِ بْنِ إِسْمَاعِيلَ، يَرْوِي الْمَوْضُوعَاتِ. (مجمع الزوائد ومنبع الفوائد)

It was narrated by al-Tabarani in al-Saghir and al-Awsat from his Shaykh: Muhammad bin Sahl al-Muhajir, Muammal bin Ismail. In al-Mizan: Muhammad bin Sahl from Muammal bin Ismail, he narrates fabrications. (Imam Noorud-deen al-Haythami 807H, Majma al-Zawaid).

محمد بن سهل العسكري. عن مؤمل بن إسماعيل. راو للموضوعات. (ميزان الاعتدال في نقد الرجال)

Muhammad bin Sahl al-Askari from Muammal bin Ismail. He is a narrator of fabrications. (Imam Shams al-Deen al-Dhahabi 748H, Mizan al-Itidal).

Imam al-Dhahabi also mentioned that Muammal bin Ismail narrates fabrications. When we find such narrators in a chain then the Hadith is considered a fabrication. These details are clarified in the science of Usool al-Hadith. Which is a useful science to study for all Muslims who read or forward Hadith.

Fabrications in writing

We believe that all people other than Prophets make mistakes. This includes scholars. It is strictly prohibited to consider scholars infallible. Therefore, we should not be shocked to find a scholar making a mistake with a Hadith narration. Especially if it is in the midst of delivering a speech or lesson.

However, we should be more concerned when the mistake is in writing. Be that a book, Fatwa or article. Since the one who is writing tends to have the ability to confirm from the original sources. Which is not practical during a speech or a lesson.

Therefore, writing a fabrication like, ‘Whoever does not make a lot of Dhikr has no Iman,’ is much worse than doing so in a speech or lesson. Although both are extremely problematic. As well as this, the scholar in question misquoted the fabrication. This demonstrates a deep ignorance of Hadith authenticity and accuracy.

And Allah Most High Knows Best.

–Answered by Shaykh Noorud-deen Rashid