The need of a spiritual master

In all reliable books of spiritual wayfaring the need of a spiritual master and mentor who supervises the journey of the traveller is prescribed. In one of his lessons Imam Khomeini stated that this [spiritual] path can not be travelled without a spiritual master (ostad). Ayatollah Qadhi (the spiritual master of Ayatollah Behjat, Allamah Tabatabai and many other contemporary Urefa) has said:

If you spend 30 years looking for a master it is worthy and in the first encounter you have travelled half the journey.

Regarding the mandatory need of the spiritual wayfarer for a master the martyred mystic Najm al-Din Razi has a very enlightening metaphor:

Reality (haqiqat) is like a pearl in the depth of the ocean. Anyone who wants the pearl must set onboard a ship to reach it. In this way any person who enters Islam and his tongue utters the confession of faith (shahadatayn) and he is firm in abiding to the Shari’ah and its laws is like a person who has entered the ocean and thus has no other option but to board the ship to reach the pearl. But it must be known that every ship needs a captain who is acquainted with the laws and ways of the ocean and knows the location of the parl. The [spiritual] wayfarer must be under the supervision of a captain of this important ship in order to reach the pearl of reality.

(References: Ayatollah Seyyed Mahdi Shams al-Din, “Hadithe Deltangi” p.62 and p.56)