Praise be to Allah.
Remembering Allah, may He be exalted, may be obligatory, as in the case of takbeerat al-ihram (the takbeer said when starting the prayer), or it may be mustahabb.
It says in al-Mawsoo‘ah al-Fiqhiyyah al-Kuwaitiyyah (21/222):
The ruling on remembering Allah (dhikr), may He be exalted:
Remembering Allah (dhikr, pl. adhkaar) is something that is liked and is required from everyone, and it is encouraged in all circumstances, apart from exceptional situations as mentioned in Islamic teaching, such as when sitting to relieve oneself, when listening to the khutbah (sermon at Friday prayers) and so on.
The evidence for it being encouraged (mustahabb) is the fact that Allah has enjoined it in many verses, and He has forbidden its opposite, namely heedlessness and forgetfulness. He has connected success to constantly remembering Him a great deal. He has praised those who do that and described them as being those who benefit from His signs, and stated that they are people of understanding. He has told us of the loss of those who are distracted from dhikr by other things. He has told us that the reward of those who remember Him is that He Himself remembers them and mentions them. He has told us that remembrance of Him is greater than everything, and He has described dhikr as being the twin of righteous deeds. He has made dhikr the beginning and end of righteous deeds in many verses, some of which we shall quote here, but we will not list all of them.
In some situations, remembrance of Allah is more highly recommended, as we shall see below.
Dhikr may be obligatory; obligatory adhkaar include some of the adhkaar of the prayer, such as takbeerat al-ihraam and recitation of Qur’an. Obligatory adhkaar also include the adhaan and iqaamah, according to the view that they are a communal obligation (fard kifaayah). Returning greetings of salaam, and saying Bismillah when slaughtering an animal for meat are also obligatory adhkaar. Details on the rulings on each of these may be found elsewhere.
Dhikr may be haraam (prohibited) if it involves elements of shirk (associating others with Allah), such as the Talbiyah of the Jaahiliyyah, or if it contains phrases that are inappropriate when speaking of Allah, such as what they used to say (in the prayer) at the beginning of Islam, “Peace be upon Allah from His slaves.” The Prophet (blessings and peace of Allah be upon him) said: “Do not say, ‘Peace (as-salaam) be upon Allah,’ for Allah is as-Salaam. Rather say: ‘At-tahiyyaatu Lillahi wa’s-salawaatu wa’t-tayyibaat (All compliments, prayers and pure words are due to Allah).’” For salaam (peace) is only sought for the one who needs it, but Allah is as-Salaam; so salaam is to be sought from Him, not for Him. Rather He is to be praised for being as-Salaam, such as saying, “Allaahumma anta al-salaam wa minka al-salaam (O Allah, You are al-Salaam (the One Who is free from all defects and deficiencies) and from You is all peace).”
Dhikr may be haraam in certain circumstances, such as saying dhikr during the khutbah (sermon) on Fridays. End quote.
The believer who prays regularly, offering the obligatory prayers on time, is constantly remembering Allah, may He be exalted, as he is reciting the adhkaar that are to be recited during the prayer, and after the prayer, and so on.
Situations in which one should make sure not to forget to recite dhikr include: eating and drinking, entering and exiting. So when a person eats or drinks something, he should mention the name of Allah (by saying Bismillah), and when he finishes it, he should praise Him (by saying Al-hamdu Lillah). When he enters his house he should mention the name of Allah, when he exits his house, he should mention the name of Allah. Similarly, he should consistently recite the adhkaar of morning and evening, and the adhkaar for going to sleep.
As for the hypocrite who conceals disbelief whilst making an outward display of being Muslim, or he is uncertain and has doubts about the religion, he is not keen to remember Allah and does not feel at ease with dhikr, apart from what he does by way of showing off and hypocrisy.
Allah, may He be exalted, says (interpretation of the meaning):
“Verily, the hypocrites seek to deceive Allah, but it is He Who deceives them. And when they stand up for As-Salat (the prayer), they stand with laziness and to be seen of men, and they do not remember Allah but little”
Ibn Katheer (may Allah have mercy on him) said: With regard to the words “And when they stand up for As-Salat (the prayer), they stand with laziness and to be seen of men, and they do not remember Allah but little”: This is how the hypocrites are in the noblest and best of deeds, namely the prayer. When they stand up to pray, they stand with laziness, because they have no sincere intention concerning it; they do not believe in it, they do not fear Allah, and they do not understand its meaning. Ibn Mardawayh narrated, via ‘Ubaydullah ibn Zahr, from Khaalid ibn Abi ‘Imraan, from ‘Ataa’ ibn Abi Rabaah, from Ibn ‘Abbaas who said: It is makrooh for a man to stand up to pray with laziness; rather he should stand up to pray cheerfully, with eagerness and joy, for he is conversing with Allah, may He be exalted, and Allah is before him, forgiving him, answering him when he calls upon Him. Then Ibn ‘Abbaas recited this verse: “And when they stand up for As-Salat (the prayer), they stand with laziness.”
Similar reports were narrated via more than one isnaad, from Ibn ‘Abbaas.
The words “And when they stand up for As-Salat (the prayer), they stand with laziness” describe their outward appearance, as Allah says elsewhere (interpretation of the meaning): “and that they came not to As-Salat (the prayer) except in a lazy state” [at-Tawbah 9:54]. Then He, may He be exalted, mentions the real motive in their hearts: “and to be seen of men”. That is, there is no sincerity towards Allah in what they do; rather they only attend the prayer by way of dissimilation and going along with people. Hence they often stay away from prayers in which they are not usually seen, such as ‘Isha’ prayer, when it is dark, and Fajr prayer when it is still dark. It is proven in as-Saheehayn that the Messenger of Allah (blessings and peace of Allah be upon him) said: “The most burdensome prayers for the hypocrites are ‘Isha’ prayer and Fajr prayer. If they knew what (reward) is in them, they would come to them even if they had to crawl. I was thinking of ordering that the call to prayer be given, then I would tell a man to lead the people in prayer, and I would go out with men carrying bundles of wood to people who do not come to the prayers, and I would burn their houses with fire around them.”
The phrase “and they do not remember Allah but little” refers to their prayers. They do not focus in the prayer, and they do not understand what they are saying; rather they are distracted from their prayer, and they have no interest in what they could attain of goodness therein.
Imam Maalik narrated from al-‘Alaa’ ibn ‘Abd ar-Rahmaan, that Anas ibn Maalik said: The Messenger of Allah (blessings and peace of Allah be upon him) said: “That is the prayer of the hypocrite, that is the prayer of the hypocrite, that is the prayer of the hypocrite. He sits watching the sun until, when it is between the horns (that is, the two sides of the head) of the Shaytaan, he pecks out four rak‘ahs, in which he does not remember Allah but little.
This is how it was narrated by Muslim, at-Tirmidhi and an-Nasaa’i, from the hadith of Ismaa‘eel ibn Ja‘far al-Madani, from al-‘Alaa ibn ‘Abd ar-Rahmaan. At-Tirmidhi said: It is hasan saheeh. End quote from Tafseer Ibn Katheer (2/438).
Abu Hayyaan (may Allah have mercy on him) said:
Al-Hasan said: It is little, because they do not do it for the sake of Allah. Qataadah said: Rather what is meant is that it is little because it is not going to be accepted, and whatever Allah rejects, a lot of it is little, and what He accepts, a little of it is a lot. Others said: It is little in relation to how much they indulge in falsehood, lies and disbelief. Az-Zamakhshari said: It is “but little” because they do not pray at all when they are away from people; they only pray in front of people, and what they pray openly is little, because whenever they have the opportunity to refrain from doing what they have no interest in, they use that opportunity. Or they do not mention Allah in the sense of reciting tasbeeh (saying Subhaan-Allah (glory be to Allah) and tahleel (saying Laa ilaaha ill-Allah (There is no god but Allah)) except a little. It may be that little means nothing at all. End quote.
But it is not possible that it means nothing at all, because it says “but” or “except”, and there cannot be an exception when there is nothing in the first place. It was also suggested that it is little because their intention (when remembering or mentioning Allah) is worldly gain, because the enjoyment of this world is little. And it was also said that there is something implied and not explicitly mentioned, which is that they do not remember the punishment and reward of Allah except a little, because they are too preoccupied with worldly concerns and they pay no attention at all to matters of the hereafter.
What appears to be the case is that dhikr here refers to remembering and mentioning Allah verbally, and that they rarely mention Allah, unlike the sincere believer, who remembers Allah, may He be exalted, most of the time.
End quote from al-Bahr al-Muheet (4/110).
This is the situation of the hypocrite. As for the believer who loves Allah and His Messenger, and is certain of the truth of His religion, he inevitably remembers Allah all the time. Even if he only recites a little dhikr, he cannot be a hypocrite in the sense mentioned above, but he is missing out on a great deal of reward and goodness by only remembering Allah a little.
Remembering Allah (dhikr) brings great benefits, such as spiritual well-being, tranquillity and softening of the heart. Allah, may He be exalted, says (interpretation of the meaning):
“Those who believe (in the Oneness of Allah - Islamic Monotheism), and whose hearts find rest in the remembrance of Allah, Verily, in the remembrance of Allah do hearts find rest”
“Is he whose heart Allah has opened to Islam, so that he is in light from His Lord (as he who is non-Muslim)? So, woe to those whose hearts are hardened against remembrance of Allah! They are in plain error!”
Another of these benefits is attaining great reward by doing a small deed, which is simply moving one’s lips and reciting a few words.
Imam an-Nawawi (may Allah have mercy on him) said in his great book, Riyadh as-Saaliheen:
Chapter on the virtue of dhikr and encouragement to remember Allah:
Allah, may He be exalted, says (interpretation of the meaning):
“and the remembrance of Allah is greater”
“Therefore remember Me (by praying, glorifying, etc.). I will remember you”
“And remember your Lord by your tongue and within yourself, humbly and with fear without loudness in words in the mornings, and in the afternoons and be not of those who are neglectful”
“and remember Allah much, that you may be successful”
“and the men and the women who remember Allah much with their hearts and tongues Allah has prepared for them forgiveness and a great reward (i.e. Paradise)”
“O you who believe! Remember Allah with much remembrance.
And glorify His Praises morning and afternoon (the early morning (Fajr) and Asr prayers)”
And there are many similar, well-known verses.
It was narrated that Abu Hurayrah (may Allah be pleased with him) said: The Messenger of Allah (blessings and peace of Allah be upon him) said: “Two words that are light on the tongue and heavy in the balance and beloved to the Most Merciful: Subhaan Allaahi wa bi hamdihi Subhaan Allaah il-‘Azeem (Glory and praise be to Allah, glory be to Allah the Almighty).”
And it was narrated that Abu Hurayrah (may Allah be pleased with him) said: The Messenger of Allah (blessings and peace of Allah be upon him) said: “When I say ‘Subhaan Allah, wa’l-hamdu Lillah, wa laa ilaah ill-Allah, wa Allahu akbar (Glory be to Allah, praise be to Allah, there is no god except Allah, and Allah is Most Great)’, this is more beloved to me than all that the sun rises upon.” Narrated by Muslim.
And it was narrated from him that the Messenger of Allah (blessings and peace of Allah be upon him) said: “Whoever says ‘Laa ilaaha ill-Allah wahdahu laa shareeka lah, lahu’l-mulk wa lahu’l-hamd wa huwa ‘ala kulli shay’in qadeer (There is no god except Allah alone with no partner; to Him be dominion and praise, and He is Able to do all things)’ one hundred times in a day, will have reward equivalent to that of manumitting ten slaves, one hundred good deeds will be written for him, one hundred bad deeds will be erased from his record, and he will have protection from the Shaytaan all that day until evening comes; no one will do anything better than what he has done, except a man who does more than that.”
And he said: “Whoever says ‘Subhaan Allaahi wa bi hamdihi (Glory and praise be to Allaah)’ one hundred times in a day, his sins will be erased, even if they are like the foam of the sea.” Agreed upon.
It was narrated from Abu Ayyoob al-Ansaari (may Allah be pleased with him) that the Prophet (blessings and peace of Allah be upon him) said: “Whoever says ‘Laa ilaaha ill-Allaah wahdahu laa shareeka lah, lahu’l-mulk wa lahu’l-hamd wa huwa ‘ala kulli shay’in qadeer (There is no god except Allah alone with no partner; to Him be dominion and praise, and He is Able to do all things)’ ten times will be like one who manumitted four of the children of Ismaa‘eel.” Agreed upon.
It was narrated that Abu Dharr (may Allah be pleased with him) said: The Messenger of Allah (blessings and peace of Allah be upon him) said: “Shall I not tell you of the dearest of words to Allah? The dearest of words to Allah are: Subhaan Allah wa bi hamdihi (Glory and praise be to Allah).” Narrated by Muslim.
It was narrated that Abu Maalik al-Ash‘ari (may Allah be pleased with him) said: The Messenger of Allah (blessings and peace of Allah be upon him) said: “Purification is half of faith, ‘al-hamdu Lillaah’ fills the Balance and ‘Subhaan-Allah’ and ‘al-hamdu Lillaah’ fill the space between heaven and earth.” Narrated by Muslim.
It was narrated that Sa‘d ibn Abi Waqqaas (may Allah be pleased with him) said: A Bedouin came to the Messenger of Allah (blessings and peace of Allah be upon him) and said: Teach me some words that I may say: He said: “Say: ‘Laa ilaaha ill-Allah wahdahu laa shareeka lah, Allahu akbaru kabeeran, wal hamdu Lillahi katheeran, wa subhaan Allahi Rabb il-‘Aalameen, wa la hawla wa la quwwata illa Billah il-‘Azeez il-Hakeem ( There is no god but Allah alone, with no partner or associate, Allah is most great, much praise be to Allah, glory be to Allah the Lord of the Worlds, and there is no power and no strength except with Allah, the Almighty, the Most Wise).” He said: These are for my Lord; what is there for me? He said: “Say: ‘Allahumm aghfir li wa’rhamni wa’hdini wa’rzuqni (O Allah, forgive me, have mercy on me, guide me and grant me provision).” Narrated by Muslim.
Then he narrated many other hadiths. This is a big topic.
For more information, please see the book al-Wabil as-Sayyib min al-Kalim at-Tayyib by Imam Ibn al-Qayyim (may Allah have mercy on him).
Whoever reflects upon the immense reward for these few words will understand the virtue of dhikr (remembrance of Allah). It is appropriate for every Muslim, man or woman, to be keen to remember Allah and to keep his tongue moist with dhikr and fill the record of his deeds therewith.
We ask Allah to enable us and you to do that.
And Allah knows best.