We are often Accused of praying three times a day or that combining Prayers is Haram. Unfortunately Sunni’s don’t pay much attention to the their Books or the Prophets (pbuh) Sunna. In the Quran we clearly read there are three specific times:

Holly Quran 17:78 Establish regular prayers – at the sun’s decline till the darkness of the night, and the morning prayer and reading: for the prayer and reading in the morning carry their testimony.

Following references are from Sahih Bokhari

Sahih Bokhari Volume 1, Book 10, Number 518:
Narrated Ibn ‘Abbas:

“The Prophet prayed eight Rakat for the Zuhr and ‘Asr, and seven for the Maghrib and ‘Isha prayers in Medina.” Aiyub said, “Perhaps those were rainy nights.” Anas said, “May be.”

Sahih Bokhari Volume 1, Book 10, Number 524:
Narrated Abu Bakr bin Uthman bin Sahl bin Hunaif:

that he heard Abu Umama saying: We prayed the Zuhr prayer with ‘Umar bin Abdul Aziz and then went to Anas bin Malik and found him offering the Asr prayer. I asked him, “O uncle! Which prayer have you offered?” He said ‘The Asr and this is (the time of) the prayer of Allah s Apostle which we used to pray with him.”

Sahih Bokhari Volume 1, Book 10, Number 537:
Narrated Ibn ‘Abbas:

The Prophet prayed seven Rakat together and eight Rakat together.

this is the link for sahih bokhari.

www.usc.edu/schools/college/crcc/engagement/resources/texts/muslim/hadith/bukhari/010.sbt.html

The following are hadith from Sahih Muslim on Combining Prayers:

please also note that the very name of this chapter is

Chapter 100: COMBINATION OF PRAYERS, WHEN ONE IS RESIDENT

and it is different than the previous chapter which is named

Chapter 99: PERMISSIBILITY OF COMBINING TWO PRAYERS ON A JOURNEY

the online link is also given as below.

www.usc.edu/schools/college/crcc/engagement/resources/texts/muslim/hadith/muslim/004.smt.html#004.1515

now we turn our attention to ahadeeth:-

SAHIH MUSLIM, Book 4, Number 1515: Ibn ‘Abbas reported: The Messenger of Allah (may peace be upon him) observed the noon and afternoon prayers together, and the sunset and Isha’ prayers together without being in a state of fear or in a state of journey.

SAHIH MUSLIM, Book 4, Number 1516: Ibn ‘Abbas reported: The Messenger of Allah (may peace be upon him) observed the noon and afternoon prayers together in Medina without being in a state of fear or in a state of journey. (Abu Zubair said: I asked Sa’id [one of the narrators] why he did that. He said: I asked Ibn ‘Abbas as you have asked me, and he replied that he [the Holy Prophet] wanted that no one among his Ummah should be put to [unnecessary] hardship.)

SAHIH MUSLIM, Book 4, Number 1517: Ibn ‘Abbas reported that the Messenger of Allah (may peace be upon him) combined the prayers as he set on a journey in the expedition to Tabuk. He combined the noon prayer with the afternoon prayer and the sunset prayer with the ‘Isha’ prayer. Sa’id (one of the rawis) said to Ibn ‘Abbas: What prompted him to do this? He said: He wanted that his Ummah should not be put to (unnecessary) hardship.

SAHIH MUSLIM, Book 4, Number 1518: Mu’adh reported: We set out with the Messenger of Allah (may peace be upon him) on the Tabuk expedition, and he observed the noon and afternoon prayers together and the sunset and ‘Isha’ prayers together.

SAHIH MUSLIM, Book 4, Number 1519: Mu’adh b. Jabal reported: The Messenger of Allah (may peace be upon him) combined in the expedition to Tabuk the noon prayer with the afternoon prayer and the sunset prayer with the ‘Isha’ prayer. He (one of the narrators) said: What prompted him to do that? He (Mu’adh) replied that he (the Holy Prophet) wanted that his Ummah should not be put to (unnecessary) hardship.

SAHIH MUSLIM, Book 4, Number 1520: Ibn ‘Abbas reported that the Messenger of Allah (may peace be upon him) combined the noon prayer with the afternoon prayer and the sunset prayer with the ‘Isha’ prayer in Medina without being in a state of danger or rainfall. And in the hadith transmitted by Waki’ (the words are): “I said to Ibn ‘Abbas: What prompted him to do that? He said: So that his (Prophet’s) Ummah should not be put to (unnecessary) hardship.” And in the hadith transmitted by Mu’awiya (the words are): “It was said to Ibn ‘Abbas: What did he intend thereby? He said he wanted that his Ummah should not be put to unnecessary hardship.”

SAHIH MUSLIM, Book 4, Number 1521: Ibn ‘Abbas reported: I observed with the Apostle of Allah (may peace be upon him) eight (rak’ahs) in combination, and seven rak’ahs in combination. I (one of the narrators) said: O Abd Sha’tha’, I think that he (the Holy Prophet) had delayed the noon prayer and hastened the afternoon prayer, and he delayed the sunset prayer and hastened the ‘Isha’ prayer. He said: I also think so.

SAHIH MUSLIM, Book 4, Number 1522: Ibn ‘Abbas reported that the Messenger of Allah (may peace be upon him) observed in Medina seven (rak’ahs) and eight (rak’ahs), i.e. (be combined) the noon and afternoon prayers (eight rak’ahs) and the sunset and ‘Isha’ prayers (seven rak’ahs).

SAHIH MUSLIM, Book 4, Number 1523: ‘Abdullah b. Shaqiq reported: Ibn ‘Abbas one day addressed us in the afternoon (after the afternoon prayer) till the sun disappeared and the stars appeared, and the people began to say: Prayer, prayer. A person from Banu Tamim came there. He neither slackened nor turned away, but (continued crying): Prayer, prayer. Ibn ‘Abbas said: May you be deprived of your mother, do you teach me Sunnah? And then he said: I saw the Messenger of Allah (may peace be upon him) combining the noon and afternoon prayers and the sunset and ‘Isha’ prayers. ‘Abdullah b. Shaqiq said: Some doubt was created in my mind about it. So I came to Abu Huraira and asked him (about it) and he testified his assertion.

SAHIH MUSLIM, Book 4, Number 1524: ‘Abdullah b. Shaqiq al-‘Uqaili reported: A person said to Ibn ‘Abbas (as he delayed the prayer): Prayer. He kept silence. He again said: Prayer. He again kept silence, and he again cried: Prayer. He again kept silence and said: May you be deprived of your mother, do you teach us about prayer? We used to combine two prayers during the life of the Messenger of Allah (may peace be upon him).