A new Muslimah is doubtful about the obligation of wearing hijab when praying

Praise
be to Allah.

First of all, we would like to congratulate you for the
blessing of Islam and faith, and we ask Allah, may He be exalted, to bless
you and guide you in this world and the hereafter. 

You should understand that the wise person is the one who is
fair-minded and thinks objectively, paying attention to all angles of the
matter he is examining, so that he will not fall prey to contradiction:
today he finds himself doubting the reason why he should cover up when
praying, but if the Sunnah was to be uncovered when praying, he would soon
find himself having doubts and questioning the reason why one should uncover
oneself too. So when Islam enjoins covering up he objects to it, and if it
were to enjoin uncovering he would object, and so on. On this website, we
hear about the thoughts of confused and troubled people a great deal, as
they are living in a vicious circle to which there is no end unless they
block the whispers of the Shaytaan, otherwise the Shaytaan may well impact
their religious and worldly affairs. 

All people understand that the issue of clothing differs from
one situation to another. The workplace and formal occasions are not like
leisure trips or being at home. A person’s situation in this world is not
like his situation in the grave, beneath the earth; whoever thinks that
these situations should be alike is contradicting sound reasoning, and will
end up thinking that these rational standards contradict one another, but
his thinking is not based on any rational or shar‘i principles. 

By the same token, in your question you want to compare your
situation when standing before Allah in prayer to your situation in the
grave or on the Day of resurrection, or to your situation when you are
wearing house clothes or pyjamas! Not only that, you think that this wrong
analogy is becoming a serious problem in your mind, and a catastrophe that
you cannot stop thinking about, to such an extent that doubts have begun to
creep into your heart. This is a sign of lack of reasoning which requires
you to ponder and think about it, so that you do not let it affect your
affairs in this world, let alone the hereafter. 

Fine, if you want to draw analogies, which situations will
you choose? 

Would you prefer to pray naked, as your mother bore you and
as you will be gathered on the Day of Resurrection? 

Or do you want to pray in a shroud whilst you are still alive
in this world, as the deceased is wrapped in his shroud? 

The situation you are looking for is not what Allah has
prescribed, neither is it akin to the situation of the deceased in his grave
or the situation of people on the Day of Resurrection. You are not following
the conclusions of your own analogy or the teachings of Islam. 

Let us say that there is no good reason for all of that, and
there is nothing that deserves all this thought or doubts. The matter is far
too insignificant for that. If you were to ask any wise person about the
wisdom behind Muslim men and women covering when they pray, he would not
hesitate to tell you that it is for the purpose of showing respect, being
modest and observing proper etiquette before Allah, may He be glorified,
when standing before Him and communicating with Him. It is something
wonderful to stand before Him, may He be glorified and exalted, when you are
fully dressed in the manner that He asks of you and that He loves for you,
which is to wear hijab and to cover the head in particular, as well as the
rest of the body. Allah, may He be glorified and exalted, says
(interpretation of the meaning):

“O Children of Adam! Take your adornment (by wearing your
clean clothes), while praying and when going round (the Tawaaf of) the
Ka‘bah, and eat and drink but waste not by extravagance, certainly He
(Allah) likes not Al-Musrifoon (those who waste by extravagance)”

[al-A‘raaf 7:31].

What is meant by “while praying” is at the time of
every prayer, whether it is in the mosque or otherwise. 

Al-‘Allaamah as-Sa‘di (may Allah have mercy on him) said:
That is, cover your ‘awrah at the time of all prayers, obligatory or
voluntary, for covering it is adornment for the body, whereas uncovering
leaves the body unpleasing and off-putting. 

It may be that what is meant by adornment here is more than
merely covering, namely clean and proper clothing. This indicates that it is
enjoined to cover the ‘awrah when praying and to choose nice clothes for it,
and keeping that clothing clean and free of dirt and impurities.

End quote from Tayseer al-Kareem ar-Rahmaan (p. 287) 

Prayer is a serious matter, in which one is standing before
Allah; the Muslim slave converses in the prayer with his Lord, focusing his
mind and heart on his Lord and Creator, with presence of mind, humility and
tranquillity, hoping for His mercy and fearing His punishment; he places his
head and nose on the ground in humility before Allah, may He be glorified
and exalted. In this important situation, nothing is befitting except for
the Muslim man or woman to be completely and properly clothed, in garments
that befit a meeting with the King of kings, may He be glorified and
exalted, not in night clothes or work clothes. 

Moreover, you have to realise and have a firm belief – as you
are a sincere Muslim – that Islam means submitting and surrendering to
Allah, may He be glorified and exalted, because of what is mentioned in His
holy Book and what is narrated in the Sunnah of His Prophet Muhammad
(blessings and peace of Allah be upon him). What the Muslim must do, if he
finds himself confused and unable to see the wisdom in any matter, is to
seek the light of Revelation which will show him the way; this Revelation
which comes from Allah, may He be glorified and exalted, is to be found in
the Qur’an and Sunnah. Allah, may He be glorified and exalted, says
(interpretation of the meaning):

“O you who believe (in Moosa (Moses) (i.e. Jews) and ‘Eesa
(Jesus) (i.e. Christians))! Fear Allah, and believe too in His Messenger
(Muhammad (blessings and peace of Allah be upon him)), He will give you a
double portion of His Mercy, and He will give you a light by which you shall
walk (straight), and He will forgive you. And Allah is Oft-Forgiving, Most
Merciful”

[al-Hadeed 57:28]

“Certainly, We have brought to them a Book (the Qur’an)
which We have explained in detail with knowledge, – a guidance and a mercy
to a people who believe”

[al-A‘raaf 7:52]. 

The Muslim seeks guidance in Islamic teachings, and is not
like those of whom Allah, may He be glorified, says (interpretation of the
meaning):

“And among men is he who disputes about Allah, without
knowledge or guidance, or a Book giving light (from Allah)”

[al-Hajj 22:8].

This is one of the basic meanings of Islam, faith in Allah,
may He be glorified and exalted, and belief in His Prophet Muhammad
(blessings and peace of Allah be upon him) – not what you are doing of
doubting every little thing to the extent that you describe in your
question. There is no justification for that, for you could have continued
to pray as the Muslims do, then ask whatever questions you wanted to after
that; you should not have given in to the whispers and doubts of the
Shaytaan and stopped praying altogether. 

The Holy Qur’an is the word of Allah, and the word of Allah
is perfect, fair and precise; it has no shortcomings whatsoever. Allah, may
He be glorified and exalted, is the One Who says (interpretation of the
meaning):

“And whatsoever the Messenger (Muhammad (blessings and
peace of Allah be upon him)) gives you, take it, and whatsoever he forbids
you, abstain (from it) , and fear Allah. Verily, Allah is Severe in
punishment”

[al-Hashr 59:7]. 

The Prophet (blessings and peace of Allah be upon him)
instructed women to cover themselves when praying, and to wear hijab and
cover their heads. It is proven from ‘Aa’ishah (may Allah be pleased with
her) that the Prophet (blessings and peace of Allah be upon him) said:
“Allah does not accept the prayer of any woman who menstruates unless (she
wears) a head cover.” [What is meant by a “woman who menstruates” here is a
woman who has reached the age of menstruation, not a woman who actually has
her menses.]

See Ma‘aalim as-Sunan (1/180). Narrated by Abu Dawood
in as-Sunan (641); at-Tirmidhi in as-Sunan (277) – he said: It
is a hasan hadeeth. The ruling of the scholars based upon this hadeeth is
that when a woman reaches the age of puberty, if she prays with any part of
her hair uncovered, then her prayer is not valid. 

Ibn al-Mundhir (may Allah have mercy on him) said: 

They were unanimously agreed that the free adult woman must
cover her head when she prays, and that if she prays with all of her head
uncovered, then she must repeat the prayer.

End quote from al-Ijmaa‘ (p. 43) 

If you do not want to follow the Prophet’s Sunnah with regard
to this matter, then why do you pray Zuhr with four rak‘ahs, when you will
not find this number in the Book of Allah? Why do you give zakaah at a rate
of 2.5%, when you will not find this number in the Qur’an either? In fact
the Muslims take all of those numbers from the saheeh Sunnah of the Prophet
(blessings and peace of Allah be upon him), for Allah, may He be exalted,
says (interpretation of the meaning):

“Nor does he speak of (his own) desire.

It is but a revelation revealed”

[an-Najm 53:3-4]. 

Our scholars (may Allah have mercy on him) said that the
verse “while praying” [al-A‘raaf 7:31]
is one of the teachings of the Qur’an that helped primitive nations to
become civilised. Just as the Arabs during the Jaahiliyyah used to
circumambulate the Ka‘bah naked, many nations did not have the culture of
wearing clothing and adorning themselves with clothing. By requiring people
to dress fully, Islam became one of the means of those nations taking a huge
leap forward in terms of civilisation. 

Al-‘Allaamah Muhammad Rasheed Rida (may Allah have mercy on
him) said: 

This instruction to wear adornment “while praying” –
and not only in al-Masjid al-Haraam – is one of the basic principles that
form a sound foundation for a person’s religious and worldly affairs. Some
of the value of this principle may be understood from the reports that speak
of the reason for revelation of these verses. Indeed, in order to fully
appreciate its value we need to know something of the history of nations and
religions, and to understand that most wild peoples who live in the bush and
in the jungle, as individuals or in groups, and live in caves, and many idol
worshipping tribes who live on ocean islands and African mountains all live
naked, both women and men. But whenever Islam reached any of these peoples,
it taught them to wear clothes by making it obligatory to cover themselves
and adorn themselves. When some European missionaries went to extremes in
criticising Islam in order to put people off it and turn them away from it,
and to incite Europe against the Muslims, one fair-minded person among them
responded by reminding them that the spread of Islam in Africa was in fact a
blessing to Europe, because it had spread civility among the people by
making them give up nakedness and obliging them to wear clothes, and this
was the reason for the European textile industry finding a market among
them! 

Indeed I say that there are some idol worshipping nations
that have a strong civilisation and a high level of various branches of
knowledge and the arts, but most of them live naked, but when any of them is
guided to Islam, they begin to wear clothes and adorn themselves, then they
begin to make clothes. Then their idol-worshipping neighbours begin to
imitate them to some extent. Thus we see India, whose civilisation was
highly developed in the past and at present, despite the prevalence of idol
worship; you still find thousands of their women and men fully naked or half
naked or three quarters naked. You see some of the men in stores and
factories almost naked, covering only the private parts, or only covering
the lower half of the body; and a woman may leave her belly, thighs or the
upper part of her body – all or some of it – uncovered. Some of their
fair-minded scholars have admitted that the Muslims are the ones who taught
them to wear clothes and to eat from vessels. Many of the poor people still
put food on leaves and eat from them. But they are better off than many
other polytheists in terms of covering and adornments, because the Muslims
used to rule them, and Indian Muslims are still among the most advanced
Muslims on Earth in terms of knowledge, deeds and influence over the
idolaters in their country. 

As for the Muslims further east, where ignorance is
prevalent, they are closer to the idolaters than to the Muslims in terms of
the way they dress and in many of their religious rituals. An example is the
Muslim women of Thailand who do not regard any part of the body as ‘awrah
apart from the private parts, as mentioned above. Wherever Islam grows
stronger, then you will find that covering and adornment that is befitting
of human dignity and civility. 

Whoever understands this will realise the value of this
important principle in Islam. Were it not for the fact that this most
civilised faith made clothing and adornment part of the religion of Allah –
i.e., He made it obligatory upon His slaves – it would not have transformed
so many nations and peoples, leading them from extreme wildness to refined
civility. The one who does not recognise this blessing is the one who is
ignorant of history, even if he claims to have knowledge of it. In fact it
is not unlikely to find a westernised pretender who sits in a casino or cafe
or pub, leaning back with his hat tilted on his head, saying: What does it
mean to say that people should adorn themselves with clothes as part of
religious matters, at a time when it is necessary for all humans to cover
themselves and there is no need for divine revelation or a religious decree?

End quote from Tafseer al-Manaar (8/340-341) 

On our website we have previously published a number of
fatwas which explain how a woman should dress for prayer; please see the
following questions: 11073,
69804, 32993

To sum up: 

Prayer in which one stands before Allah is something of great
importance which requires the Muslim woman to wear complete hijab, paying
attention to proper etiquette before Allah. This is something other than the
clothes that one wears at home, which is light clothing. Moreover, the
Muslim receives light and guidance from the Holy Qur’an and saheeh Sunnah,
so he should not make his views and doubts judge of the revelation that
comes from Allah. 

And Allah knows best.