Imām Ibn Qayyim (رحمه الله) stated:

The continuous remembrance of Allāh [i.e. adkhār] is a protection from hypocrisy, since the hypocrites rarely remember Allāh. Allāh said about them:

وَلَا يَذْكُرُونَ اللَّـهَ إِلَّا قَلِيلًا
“And they only remembered Allāh occasionally”
[Al-Nisāʾ, 4:142].

Kaʿb (رحمه الله) said: “Whoever continuously remembers Allāh is free from hypocrisy.” Consequently, Allāh concluded Sūrah al-Munāfiqūn [i.e. The Sūrah of the Hypocrites] by saying:

يَا أَيُّهَا الَّذِينَ آمَنُوا لَا تُلْهِكُمْ أَمْوَالُكُمْ وَلَا أَوْلَادُكُمْ عَن ذِكْرِ اللَّـهِ ۚ وَمَن يَفْعَلْ ذَٰلِكَ فَأُولَـٰئِكَ هُمُ الْخَاسِرُونَ
“O you who believe! Let not your wealth or your children divert you from the remembrance of Allāh, and whoever does that then they are the losers”
[Al-Munāfiqūn, 63:9].

This is a warning from the fitnah of the hypocrites who fell into hypocrisy because they failed to remember Allāh.

Questioned about the Khawārij¹, some of the Companions said: “They are not hypocrites as the hypocrites hardly remember Allāh.” Therefore, remembering Allāh continuously is a protection from hypocrisy, and only remembering Him occasionally is a sign of hypocrisy.

Allāh does not test the heart by filling it with hypocrisy as He is more honourable than that; rather, the heart is filled with hypocrisy because it has forgotten Allāh’s remembrance.

Endnotes:

1. One of the earliest deviant groups of which the Prophet (ﷺ) said about them:

يَخْرُجُونَ مِنَ الدِّينِ كَمَا يَخْرُجُ السَّهْمُ مِنَ الرَّمِيَّةِ ثُمَّ لاَ يَعُودُونَ فِيهِ هُمْ شَرُّ الْخَلْقِ وَالْخَلِيقَةِ

“They will pass clean through the religion just as the arrow passes through the prey, and they will never come back to it. They would be the worst among the creation and the creatures.” (Saḥīḥ Muslim 1067 from Abu Dharr)

Source: al-Wābil al-Ṣayyib, pg. 80.
Translated by: Abū Wāʾil Musa Shaleem