Praise be to Allah.
What the Muslim must do is memorize Soorat al-Faatihah, because no prayer is valid without it, as is narrated in as-Saheehayn [al-Bukhaari and Muslim] from ‘Ubaadah ibn as-Saamit that the Messenger of Allah (blessings and peace of Allah be upon him) said: “There is no prayer for the one who does not recite the Opening of the Book (al-Faatihah).”
Al-Bukhaari (756) and Muslim (394).
In the hadith about the one who prayed badly, the Prophet (blessings and peace of Allah be upon him) said: “When you stand to pray, say takbeer [“Allahu akbar”], then recite whatever you can of the Qur’an.”
Narrated by al-Bukhaari (757) and Muslim (397).
It is not valid to recite Qur’an in any language other than Arabic, because when the Qur’an is translated, it is no longer Qur’an; rather it is a tafseer (explanation) of Qur’an. Hence the majority of fuqaha’ are of the view that it is obligatory to recite Qur’an in Arabic in prayer, and that recitation is not valid except in Arabic.
This is in contrast to the view of Abu Haneefah (may Allah have mercy on him), who regarded it as valid to recite in a language other than Arabic, but his two companions – Abu Yoosuf and Abu Muhammad – restricted the permissibility of doing so to one who is unable to learn Arabic.
It says in Tabyeen al-Haqaa’iq Sharh Kanz ad-Daqaa’iq (1/110):
With regard to reciting in Farsi, it is permissible according to the view of Abu Haneefah.
Abu Yoosuf and Muhammad said: It is not permissible if the person is able to recite in Arabic, because the word Qur’an refers to the text that was revealed in Arabic, as Allah, may He be exalted, says (interpretation of the meaning): “Indeed, We have made it an Arabic Qur'an” [as-Zukhruf 43:3] and “Indeed, We have sent it down as an Arabic Qur'an” [Yoosuf 12:2]. This refers to the language of the Qur’an. End quote.
Ibn Qudaamah (may Allah have mercy on him) said: It is not acceptable to recite in any language other than Arabic, or to replace any of its phrases with another Arabic phrase, regardless of whether a person can recite in Arabic or not. This is the view of ash-Shaafa‘i, Abu Yoosuf and Muhammad.
Abu Haneefah said: That is permissible. Some of his companions said: It is only permissible for one who does not speak Arabic. He quoted as evidence the verse in which Allah, may He be exalted, says (interpretation of the meaning): “And this Qur'an was revealed to me that I may warn you thereby and whomever it reaches” [al-An‘aam 6:19]. And it is not possible to warn any people except in their own language.
Moreover, Allah, may He be exalted, says (interpretation of the meaning): “as an Arabic Qur'an” [Yoosuf 12:2] and “In a clear Arabic language” [ash-Shu‘araa’ 26:195]. Moreover, the Qur’an is a miracle in both its wording and its meanings, and if it is changed it is no longer Qur’an or like Qur’an; rather it is a tafseer (explanation) of it, and if its explanation were like it, that would mean that they would be able to bring something like it, but Allah challenged them that they would not be able to bring a soorah like it.
Section: If a person is unable to recite in Arabic, then he must learn, and if he does not do that when he is able to, then his prayer is not valid. If he is not able to do that or he fears that the time for the prayer will end, and he knows one verse of al-Faatihah, then he must repeat it seven times. …
If he is not able to recite any part of it, and he has memorized anything else of the Qur’an, he should recite something of equivalent length, if he is able to, and it is not acceptable for him to do anything else, because of the report narrated by Abu Dawood, from Rifaa‘ah ibn Raafi‘, that the Prophet (blessings and peace of Allah be upon him) said: “When you stand to pray, if you know anything of the Qur’an, then recite it, otherwise praise Allah [say “al-hamdu Lillah (praise be to Allah)”], proclaim His oneness [say “Laa ilaaha ill-Allah (There is no god but Allah)”] and magnify Him [say “Allahu akbar (Allah is Most Great)”].” That is because such words are similar to the meaning of al-Faatihah, so that is more appropriate. And he must recite as many phrases as the number of verses of al-Faatihah.
If he cannot recite anything of the Qur’an and cannot learn before the time for the prayer ends, then he must say “Subhaan Allah, wa’l-hamdu Lillah, wa laa ilaaha ill-Allah, wa Allahu akbar, wa laa hawla wa quwwata illa Billah (Glory be to Allah, praise be to Allah, there is no god but Allah, Allah is most great, and there is no power and no strength except with Allah), because of the report narrated by Abu Dawood, who said: A man came to the Prophet (blessings and peace of Allah be upon him) and said: I cannot memorise anything of the Qur’an; teach me of it what will be sufficient for me. He said: “Say: ‘Subhaan Allah, wa’l-hamdu Lillah, wa laa ilaaha ill-Allah, wa Allahu akbar, wa laa hawla wa quwwata illa Billah (Glory be to Allah, praise be to Allah, there is no god but Allah, Allah is most great, and there is no power and no strength except with Allah).’” The man said: This is for Allah; what is there for me? He said: “Say: ‘Allahumm aghfir li, wa’rhamni, wa’rzuqni, wa’hdini, wa ‘aafini (O Allah, forgive me, have mercy on me, grant me provision, guide me and pardon me).’”
End quote from al-Mughni (1/350).
With regard to reciting more than al-Faatihah, it is not obligatory.
With regard to the takbeer (saying “Allahu akbar (Allah is most great)”), tasbeeh (saying “Subhaan Allah (Glory be to Allah)”) and tashahhud (the words recited when sitting in the prayer), it is obligatory to learn these words and recite them in Arabic; if one is not able to do that, that he may recite them in his own language, according to the majority of fuqaha’.
With regard to what you have been doing of praying and reciting Qur’an in English, there is the hope that you will be rewarded for it and will not be blamed for it, because you were unaware of the ruling, and taking into account the view of those scholars who regard it is valid to recite in a language other than Arabic.
But from now on, you have to stop reciting Qur’an in prayer in any language other than Arabic, and you must learn al-Faatihah and some short soorahs or verses that you are able to learn, and recite them in your prayer.
There is no reason why you should not read a translation of the meanings of the Qur’an outside of prayer; in fact you should do that, so as to increase your understanding and gain knowledge. See the answer to question no. 1690.
And Allah knows best.a