Bismillahir Rahmanir Rahim

Nahmaduhu wa Nusalli ‘alaa Rasulihil Kareem,

wa ‘alaa Aalihi wa Sahbihi wa Awliyaaihi ajma’een.

Allahu ta ‘ala has commanded us to keep the company of pious people, to visit them to learn from them, to benefit from them and to do benefit [help] to them.  Our salvation lies in obeying the commands of Allahu ta ‘ala and His Beloved Sayyidinaa wa Mawlaana Muhammad Sall Allahu ‘alaihi wa Aalihi wa Sallim.

وَاصْبِرْ نَفْسَكَ مَعَ الَّذِينَ يَدْعُونَ رَبَّهُمْ بِالْغَدَاةِ وَالْعَشِيِّ يُرِيدُونَ وَجْهَهُ ۖ وَلَا تَعْدُ عَيْنَاكَ عَنْهُمْ تُرِيدُ زِينَةَ الْحَيَاةِ الدُّنْيَا ۖ وَلَا تُطِعْ مَنْ أَغْفَلْنَا قَلْبَهُ عَنْ ذِكْرِنَا وَاتَّبَعَ هَوَاهُ وَكَانَ أَمْرُهُ فُرُطًا [١٨:٢٨]  

And keep thy soul content with those who call on their Lord morning and evening, seeking His Face; and let not thine eyes pass beyond them, seeking the pomp and glitter of this Life; nor obey any whose heart We have permitted to neglect Our Dhikr [remembrance], one who follows his own desires, whose case has gone beyond all bounds. Suratul Kahf, 28^th Ayah.

The circumstances behind the sending down of this ayah are as follows;

Sayyidinaa Salman al-Farisi Radhi Allahu anhu who said: “Those whose hearts were to be reconciled (al-mu'allafati qulubuhum) – were 'Uyaynah ibn Hisn, al-Aqra' ibn Habis and their families – who came to the Messenger of Allah, Sall Allahu ‘alaihi wa Aalihi wa Sallim, and said: 'O Messenger of Allah, if only you could sit at the front of the assembly and remove these people - meaning: Salman al-Farisi, Abu Dharr al-Ghifari and other poor Muslims - and their smelly outer garments - because the only thing they had on them were these woolen outer garments - from us, then we could sit with you, talk to you and learn from you!' [1]

As a response, Allah, exalted is He, revealed (And recite that which hath been revealed unto thee of the Scripture of thy Lord. There is none who can change His words, and thou wilt find no refuge beside Him. Restrain thyself along with those who cry unto their Lord at morn and evening, seeking His Countenance) [18:27-28] up to His words (Lo! We have prepared for disbelievers Fire...) [18:29], threatening them with hell.

The Prophet, Sall Allahu ‘alaihi wa Aalihi wa Sallim, stood up and went looking for them. He found them at the back of the masjid making dhikr of Allah, exalted is He. He said: 'Praise be to Allah Who did not take away my soul until He commanded me to content myself with men of my community. It is with you that I live and with you that I die' ”. (…and obey not him whose heart We have made heedless of Our remembrance…) [18:28]. [Asbaabun Nuzul al Wahidi]

Allahu ta ‘ala mentions in Suratul Kahf the journey of Sayyidinaa Musa ‘alaihi salaam in search of knowledge:

Behold, Sayyidinaa Musa said to his attendant, "I will not give up until I reach the junction of the two seas or (until) I spend years and years in travel." Suratul Kahf 60^th ayah.

Imam Jalaaluddin Suyuti Rahmatullahi ‘alaihi mentions in “Tafsir Jalalayn” That the attendant of Sayyidinaa Musa  alaihi salaam, Yusha bin Nun used to follow him around serve him and learn from him as a student, keeping his company.  This is the attendant who accompanied Sayyidinaa Musa on his journey to Meet Shaykh Khidhr ‘alaihi salaam.

“And, mention, when Sayyidinaa Musa , son of Amram (‘Imrān), said to his attendant, Joshua son of Nun (Yūsha‘ bin Nūn), who used to follow him around, serve him and acquire knowledge from him, ‘I will not give up, I will not stop journeying, until I have reached the juncture of the two seas — the point where the Byzantine sea and the Persian sea meet, beyond the east, — though I march on for ages’, for a very long time before reaching it, if it be far.” [Tafsir Jalaalayn]