Among the differences between the Shia and the Sunni are the time and the date of the Night of Qadr. They also differ about this fact that which night of the year it is.
Although both the Shia and the Sunni have discrepancy in some issues related to “the Night of Qadr” and its special customs and observances, undoubtedly, such a night exists and it is significant and all Muslims concur with the existence of this night. The origin of such an agreement can be traced back to the verses of the Noble Quran, while the source of disagreements is the various interpretations of verses and narrations.
Among the differences between the Shia and the Sunni are the time and the date of the Night of Qadr. They also differ about this fact that which night of the year it is. From the Shia’s point of view, it is certainly one of the nights in the third part of the holy month of Ramadan, but there are different narrations and it is emphasized among them that most likely it is found in the eve of 19thor 21stor 23rd of Ramadan. However, there is a general and definitive agreement among Shiites in terms of its definite existence within the Ramadan.
Nevertheless, from the Sunna’s viewpoint, there are different narrations and subject matters in their sources pertaining to this issue. Firstly, there have been a certain amount of doubt and dispute among Sunnites over whether the Night of Qadr is one of the nights within the holy month of Ramadan or it could be any other night of the year. However, a group of narrations like the well-known narration of Abu Hanifain Sharh al-Azhar emphasize this belief that it is not a definite point that the Night of Qadris within these 10 nights but it is hidden among the nights of the year.
By contrast, another group of narrations indicate that the Night of Qadr is found to be one of the last ten nights of the holy month of Ramadan. In a general categorization, these narrations are categorized into three groups insisting on the 21st, 23rd and 27th of Ramadan.
The narrative Sunni sources mostly insist on the 23rd night, albeit this has been stated merely in sources. Nowadays referring to the narrations, the probability of 27thnightis considered stronger than others and special observances in the Night of Qadr are also taken place particularly on this night among Sunnites.
Now, according to this preamble, as an answer to your question, we can say that using the Noble Quran’s verses and Ahl al-bayt’s narrations, it is concluded nicely that the Night of Qadr is one single night because the word “Laylat” refers to unity and oneness in Arabic. The Night of Qadr means Night of the Measure. Additionally, several narrations have made it clear that the Night of Qadr is one night. As Zorrarah narrated, “I asked Imam Baqir(p.b.u.h) about the Night of Qadr. Imam said,“It is the night of 21st or 23rd.” I said,“Isn’t it one night?” Imam said,“It is.” I said,“Enlighten me then.” He said,“Does it really matter to do good deeds for two nights?”
The Night of Qadr may fall on different dates in different regions due to various horizons. The oneness of the Night of Qadr throughout the whole year is not meant that there is one single night in the same time for all different regions on the Earth, so that it begin sat a certain hour and also ends at a certain hour, but the oneness of the Night of Qadr throughout the whole year is meant that there is only one “Night of Qadr” for all residents of each area according to their lunar year.
The reason is that the Earth is spherical and while one of its hemispheres experiences the darkness, the other one is in the brightness. Therefore, it is absolutely impossible to experience night in allover the earth at the same and certain hours.
To put it in another way, the residents of each area commence their lunar year from the beginning of Muharram according to the special horizon of that particular area. After a few lunar months, Ramadan begins according to the special horizon of that area. In this month, the night of 19th or 21st or 23rd is the Night of Qadr for residents of that area.
The fact that residents of each area ought to determine the holy days and occasions according to the special horizon of their area is not exclusive to the Night of Qadr. Such measurement is also carried out for other Islamic holy days and occasions, e.g. Eid al-Fitr and Eid al-Adhawhich are holy days in Islam and there are acts of worship and special practices for these days. None of these festivals exceeds one day throughout the whole year. This sole day is determined by referring to the special horizon of each country in different Islamic countries and therefore, on many occasions, e.g. Eid al-Adha starts one day sooner in Saudi Arabia than it does in Iran and some other countries.
On that account, horizontal differences are not in conflict with that the Night of Qadr is different in various regions. Furthermore, this way of measuring the time for the Night of Qadr is not inconsistent with the claim of descending of angels, because all these events, which are symbols of divine special mercy on this night, take place on the Night of Qadr exclusive to residents of that particular area.As a result, God’s grace is also bestowed upon Sunnis if they keep vigil and conduct acts of worship at the nights which are most probable to be the night of Qadr as mentioned in narrations. Moreover, the Night of Qadr is not exclusive to a special group or sect of Muslims, but it is for every individual of them.
As an answer to your question which says whether this sect’s deeds will be accepted in divine presence, I have to say that from our point of view, Sunnis are part of the Muslim community and can enjoy all benefits and rewards considered by Almighty God for all Muslims. Additionally, if every Muslim conducts his regular worship correctly and sincerely, he has done his religious duties. However, the acceptance or rejection of our deeds is in God’s hands and Almighty God is merely aware of them. Accordingly, we cannot express any opinion concerning acceptance or rejection of a Muslim’s deeds.
The Night of Qadr or Laylat al-Qadr (Arabic: لَیلَة القَدر; Night of the Measure, Night of the Destiny) is the night of the revelation of the Quran and the predestination of the coming year for all persons.
An 8th-century Sunni Muslim theologian and jurist of Persian origin, who became the eponymous founder of the Hanafi school of Sunni jurisprudence, which has remained the most widely practiced law school in the Sunni tradition.
Abdullah ibnil-Miftah, Sharh al-azhar, Cairo, first volume, p 57.
Muslim Nayshaburi, sahih, dar al-fikr, Beiryt, 8th volume, p 58.
The phrase meaning, literally, “People of the House” or “Family of the House”. Within the Islamic tradition, the term refers to the family of prophet Muhammad.
The fifth Shia Imam, succeeding his father Zayn al-Abidin and succeeded by his son Ja’far al-Sadiq.
Muhammad ibn Hasan Shaykh Tusi, Tahdhib al-ahkam, Dar al-kutub al-Islamiya, Tehran, 3rd volume, p 85.
Muḥarram is the first month in the Islamic calendar.
 Also called the “Festival of Breaking the Fast”, is an important religious holiday celebrated by Muslims worldwide that marks the end of Ramadan, the Islamic holy month of fasting.
 Eid al-Adha, also called the “Festival of the Sacrifice”, is the second of two Islamic holidays celebrated worldwide each year, and considered the holier of the two.
 Ayatollah Makarim Shirazi and Ayatollah Jafar Subhani,Answering religious questions, Young Generation publications, Qum, 1383 (solar), p 500.