These four saloks are revealed by Guru Nanak Sahib (1469-1539 CE) and are recorded on page 1353 of the Guru Granth Sahib. Of these, salok one has ten lines, second and third saloks have four lines each, and salok four has three lines.

Of these four saloks, with some textual difference, the first salok is recorded with the twelfth pauri and the third and fourth saloks with the fourteenth pauri of ‘Asa Ki Var’ also. As per the pointer mahala in ‘Asa Ki Var’ Guru Nanak Sahib uttered the first salok and Guru Angad Sahib (1504-1552 CE) uttered the third and fourth saloks. The second salok appearing in Salok Sahaskriti is recorded with twenty-third pauri of ‘Majh Ki Var’ under the title of M: 2. In Kartarpur Bir,
The first compilation of the Guru Granth Sahib, also known as Adi Granth, that Guru Arjan Sahib instructed Bhai Gurdas to scribe in 1604 at Sri Ramsar, Amritsar.
this salok is preceded by the inscription ‘ੴ.’
Shabdarth Sri Guru Granth Sahib Ji, part ten, page 1353.

Textual differences
The difference noticed in the text
In the Guru Granth Sahib, some similar Sabads are recorded in more than one place. Giani Haribans Singh’s opinion regarding this is that “If a composition is recorded many times, it should not be construed that it must have been recorded due to the mistake of the scribe. Contrary to this, understand that what was pleasing to the Guru has been brought to the attention of his readers time and again.” -Adi Sri Guru Granth Sahib Darshan Nirnay Satik, part one, page 160; Regarding the variations found in the ending vowel symbols in these Sabads, he opines that this is due to musical reasons. In music, an increase or decrease in the poetic meter is quite natural. -part five, page 347. These variations may also have been kept by the Guru with the aim to make readers recite these compositions with alertness. On reviewing manuscripts and the list of variations in their texts (Path Bhedan Di Suchi, editor Randhir Singh, page 102-03), the possibility is that some of these differences could also have been due to the inattentiveness of earlier scribes. But here, it is also worth noting that these variations make no difference to the meanings of the Sabads. For example, the words ‘gāvani’ and ‘gāvahi’ have the same meaning: ‘they sing.’
of these saloks recorded at different places in the Guru Granth Sahib is as follows:

Salok 1
Salok Sahaskritipar̖ipustakjhūṭhubibhūkhantilakjojānasisabhniscainiscaudhiyāvaibinubāṭ
Asa Ki Varpaṛipustakjhūṭhbibhūkhaṇtilakujejāṇasisabhiniscaunihcaudhiāvaiviṇuvāṭ

Salok 2
Salok Sahaskrititasyajanmasyajāvadsansārasya
Majh Ki Vartasijanmasijāvatusansārasi

Salok 3
Salok Sahaskritikhyatrījānasinānakko
Asa Ki Varkhatrījāṇainānaku

Salok 4
Salok Sahaskritikrisnaṅātmahātmaṅbāsvadevasyakoījānasibhevnānakkodev
Asa Ki Varkrisnaṅātmāātmābāsvadevasiahkojāṇaibheunānakudeu

Linguistic Dimension
Bhai Kahn Singh Nabha considers Sahaskriti to be synonymous with ‘Gatha’ and accepts it as a mixture of Sanskrit, Pali, and Prakrit languages. He is of the opinion that ‘Salok Sahaskriti’ are recorded in this same language.
Bhai Kahn Singh Nabha, Mahan Kosh, page 136.

The authors of Shabdarth Sri Guru Granth Sahib Ji too consider ‘Gatha’ and ‘Sahaskriti’ to be the same linguistic form and state: Just as in the ancient times there was ‘Sanskrit’ parallel to ‘Prakrit,’ in the Guru period, an artificial language was prevalent in comparison to the common regional dialects, which was called ‘Gatha’ or ‘Sahaskriti.’ It was understood in the monasteries of saints across South Asia. It was independent of the grammatical differences between the languages ​​of the different provinces. For example, instead of regional forms like ‘karte hain, karde hain,’ (they do) ‘karanti’ was used.
Shabdarth Sri Guru Granth Sahib Ji, part four, page 1353.

According to Bhai Vir Singh, ‘sahas’ means naturally and with ease. ‘Krit’ means, composed, created, or made. Consequently, Sahaskriti means a language that can be created naturally or easily. He considers Sahaskriti as a kind of ‘Prakrit’ language similar to ‘Sanskrit.’ He writes that ‘Sanskrit’ was in fact a polished language; books were written in it. ‘Prakrit’ was spoken by the common people of the country. Earlier, it had a mixture of words from the native language and colloquial terms from the ‘Sanskrit.’ The form of ‘Prakrit,’ which developed because of some changes, was written as ‘Sahaskriti’ by Guru. This form of ‘Prakrit’ preceded the old Panjabi used in the Guru Granth Sahib. This language was used by the saints. The ‘Sahaskriti Salok’ are an example of that language. The line ‘koī paṛtā sahsā kirtā’
Guru Granth Sahib 876.
(one reads Sahaskriti) indicates that during the Guru period there was still a tradition of reading and teaching that language. Later, many variants of it developed, which eventually became old Panjabi and then new Panjabi.
Bhai Vir Singh, Sri Guru Granth Sahib Kosh, page 76.

According to Prof. Sahib Singh, the word ‘sahas’ of Sahaskriti is a Prakrit form derived from Sanskrit’s ‘sans,’ just as the Prakrit form ‘sahasa’ is derived from the word ‘sanshaya.’ So, the word ‘sahaskriti’ is a Prakrit form of the word ‘sanskrit.’ According to him, the saloks under the title ‘Sahaskriti’ are not Sanskrit. All these saloks are in Prakrit dialect.
Prof. Sahib Singh, Sri Guru Granth Sahib Darpan, part ten, page 12.

According to Giani Haribans Singh, Prakrit has vocabulary from Sanskrit, but it changes its form. Therefore, it is not suitable to understand Prakrit according to the grammar of Sanskrit.
Giani Haribans Singh, Adi Sri Guru Granth Sahib Darshan Nirnai Satik, part thirteen, page 250.

Contrary to the notion of the above scholars that ‘Sahaskriti’ is a mixed language, Sant Kirpal Singh considers ‘Sahaskriti’ to be the mother language of Sanskrit. He is of the opinion that ‘Sahaskriti’ has existed from the beginning. It is the mother of Sanskrit, and Sanskrit is born of it. ‘Sahaskriti,’ ‘Prantik Bhasha’ (regional language), and ‘Desh Bhasha’ (native language) are its different names. It has been used for commentaries on other texts including in ‘Prantik or Desh Bhasha.’ According to him, ‘sahas’ means Sheshnag
A serpent appearing in Hindu mythology.
which has a thousand mouths and ‘krit’ means poetry recited by Sheshnag. Thus, ‘Sahaskriti’ is a composition that contains both poetry and music.
Sant Kirpal Singh, Sri Guru Granth Sahib Ji Da Sampradai Tika Sri Amir Bhandar, part ten, page 19.

The above notion of ‘Sahaskriti’ presented by Sant Kirpal Singh is interesting and unique. Researchers need to pay attention to it and do further research in this area.

In the words of Dr. Ratan Singh Jaggi, the above discussion on the linguistic aspect of ‘Sahaskriti’ can be summed as: The word ‘sahaskriti’ is a Prakrit form of the word ‘sanskrit.’ It is used for the language which was formed on the lines of Sanskrit with a combination of Pali and Prakrit and was generally spoken in the monasteries of earlier Sidhs and Naths. Just as in the Medieval Age, ‘Sadhu-Bhasha’ was understood all over South Asia, before the development of Apabhransh, this language was universally accepted for spiritual deliberation. It is also known as ‘Gatha.’
Dr. Ratan Singh Jaggi, Guru Granth Vishavkosh, part one (u-cha), page 165.