S/PS

 Samasrayana or Pancha Samskara (meaning Five Purifications) is a Pañcaratra rite practiced in all forms of Vaishnavism. Samasrayana means 'to approach with all sincerity and truthfulness to Acharya'. During this rite, the acharya initiates a person, irrespective of sex, caste, social status etc., as his or her sishya. It is a commitment from the disciple that he or she will live as per the wishes of the acharya. Thus, the person gets the link to the Vaishnava tradition.

Samasrayana consists of the guru bringing the initiate into the srivaishnava flock through five steps: (1) thapaha-embossing the impression of Vishnu's sudarshana discus on the right shoulder of the initiate and of Vishnu's panchajanya conch on the left shoulder of the initiate - using an ember-heated silver seal; (2)pundraha-introducing the twelve locations in the body where Vishnu resides and thus are to be marked with the Vaishnava tilak sign; (3)dasaha tatha namaha-adding the suffix dasan (servant - of Vishnu and Ramanuja) to the initiate's name; (4)mantraha- teaching the Vaishnava mantram; (5) aradhana-initiating the disciple in the proper form of the ritual worship of Vishnu.

Males undergo the samasrayana ritual soon after their upanayana (sacred thread) ceremony or after their wedding - this varies depending on which subsect of srivaishnavism one belongs to. Females typically undergo this soon after their wedding.

Samashrayanam and Pancha samskaram are two words that are generally used interchangeably. However, their meanings slightly vary. ‘Pancha samskaram’ is performed in order to acknowledge ‘samashrayanam’. In other words, samashrayanam is the act of a shishya, and pancha samskaram is the act of an Acharya.

Samashrayanam just means ‘seeking total refuge’ (samyak aashrayanam). This is also called by the names sharanagati and prapatti. This can be done by a seeker (not necessarily human) with a qualified person capable of bestowing their needs. A warrior lady (draupadi) performed prapatti in order to get her robes; a crow (kakasura) performed sharanagati in order to get life, and so on. But in the Sri Vaishnava tradition, we perform sharanagati only for moksham and nothing else. For this, we seek the lotus feet of a qualified preceptor. That is why it is called ‘samashrayanam’. The underlying principle behind samashrayanam is Bhagavad Ramanuja’s words in his gadyatrayam. Udaiyavar (Ramanujacharya) performs sharanagati directly at the feet of Lord Ranganatha and Sriranga nachiyar on an auspicious day of Panguni-uttiram (the birth day of Sriranga nachiyar), when both of them were seated together on a single throne. At that instant, he seeks liberation for all souls who are related to him (ramanuja sambandhis). So all who desire moksham essentially approach an Acharya who comes in the lineage of the 74 simhasanadhipatis authorized by Udaiyavar to establish a relationship with himself. That way, the soul is assured of a berth in Sri Vaikuntham at the end of this body.

When a disciple approaches an Acharya for moksham, the Acharya initiates the disciple into Sri Vaishnavism by performing the pancha samskaras.

The underlying principle behind doing panchasamskaram is the pancharatra deekshaa. As per the Pancharatra Agama, deekshaa (initiation) is given to a pupil by his preceptor in order to make him eligible for the worship of Lord Vishnu. This has been widely imbibed into the SriVaishnava tradidtion and it has been made a common practice to undergo panchasamskaram at sharanagati. This is a way of establishing that the soul is henceforth a true servant of Sriman Narayana. Many scriptures starting right from the Vedas until the nectarine verses of Azhwars and Acharyas have clearly shown the importance of these five purificatory rites (already explained by other respondents) in establishing one’s identity as the servant of Vishnu.

1. One must never give up his servitude to Sriman Narayana and His devotees - meaning, one must never even think of another devata for any reason. There should not be another desire than moksham itself. So there is no question of worshipping other gods/etc.
2. One must be totally devoted to three things: one’s own Acharyan, the mantras that the Acharyan preaches, and the object of that mantra (verily Sriman Narayana).
3. One must abstain from all ill thoughts and misdeeds towards all souls - especially towards other devotees of Vishnu.
4. One must constantly contemplate on the divine qualities/pastimes of the Lord and His devotees, and live exclusively to serve them alone. All other engagements in life must be aligned to this requirement.
5. One must control their food and recreational habits in order to control their mind in engaging it as described earlier.
6. One must learn the essential tenets of the Sri sampradayam from a learned scholar (own acharyan or another scholar) and imbibe those qualities in their daily life.
7. One must always adorn the external insignia of a Sri Vaishnava (urdhva pundram, etc) so that their very sight purifies the other souls. It also helps them refrain from unwanted addictions.

There are many more things. But these are the very basic qualities (most essential)