What are the origins of the Salāt that we offer today? Did it originate with the Prophet (sws) or was it established earlier on. I have heard that the Jews used to pray like we did until the Temple of Solomon was destroyed. Could you elaborate?
The rituals of Salāt, Zakāt, Sawm and Hajj besides some other practices have been given to us by the Sunnah of the Prophet (sws). All these have existed since Abraham (sws). The Prophet (sws) was not the first to give directives about them. He only cleansed them of certain innovations (bid'ahs) which had over the years crept into them. It was for the establishment of the prayer that Abraham built the Ka‘bah as is mentioned by the Qur’ān:
O Lord I have made some of my offspring to dwell in a barren valley by Your sacred House in order O Lord! that they may establish regular prayer. (14:37)
We find the mention of this mode of worship even before Abraham (sws). While referring to the nation of the Prophet Shu‘ayb (sws), who according to some, lived much before Abraham (sws), the Qur’ān says:
They said: O Shu‘ayb does your prayer command you that we leave the worship which our fathers practised…” (11:87)
While referring to the Prophets Abraham, Isaac (sws) and Jacob (sws), the Qur’ān says:
And We made them leaders guiding [men] by Our command, and We sent them inspiration to do good deeds, to establish regular prayer and to give Zakāt. (21:73)
While describing the life of the Prophet Ismael (sws), the Qur’ān says:
And he used to enjoin on his people prayer and Zakāt. (19:55)
The Children of Israel were bound by a divine covenant to offer regular prayer, as quoted by the Qur’ān:
Allah did take a covenant from the Children of Israel, and We appointed twelve leaders among them and Allah said: I am with you if you establish regular prayer, give zakāt believe in my messengers, honour and assist them. (5:12)
Consequently, the Prophets of the Israelite tradition bade their nations to offer the prayer, as is specified by the Qur’ān.
We inspired Moses and his brother with this message: Make dwellings for your people in Egypt, and make your [own] dwellings into places of worship and establish regular prayer. (10:87)
The Prophet Moses (sws) had been told:
Verily I am Allah: There is no god but I. So serve Me [only] and establish regular prayer to remember me. (20:14)
This is what Jesus (sws) had said:
And He has made me blessed wheresoever I be, and has enjoined on me prayer and Zakāt as long as I live. (19:31)
We know from the Qur’ān that the sage Luqmān who belonged to the ancient Arab tradition bade his son to offer regular prayer which shows that this act of worship was in practice in his times as well:
O my son! establish regular prayer, enjoin what is just and forbid what is wrong. (31:17)
It is known from a Hadīth that Abū Dhar Ghafārī (rta) used to pray even before he had met the Prophet (sws). While talking to his nephew during the course of a journey, he says:
O son of my brother! I used to pray three years prior to meeting the Prophet. I asked: For whom did you pray. He replied: For Allah. I said: In what direction did you pray. He replied: In whatever direction the Almighty turned my face to. I used to offer the ‘Ishā prayer late at night. (Muslim: Kitāb al-Fadā‘il)
Similarly, Ka‘ab Ibn Luiyyī, one of the Prophet's ancestors used to address the Friday congregational prayers as is reported in history:
Ka‘ah was the first person who named Yawm al-‘Urūbah as Yawm al-Jumu‘ah (Friday). The Quraysh used to gather round him on this day. He would address them and remind them of the advent of the Prophet Muhammad (sws) and inform them that he would be from among his progeny, and would direct them to follow him and believe in him. (Ibn Manzūr, Lisān al-‘Arab, Vol 8, p. 58)
All this evidence points out that the prayer (Salāt) was an introduced form of worship in the times of the Prophet (sws). It is precisely for this reason that we find no mention of its details in the Qur’ān. The Qur’ān just seems to be referring to it as a practice which was already being followed in the society, and needed to be put in the right shape in some of its aspects.