In Hinduism, Hymns addressed to Gods/Goddesses are numerous.
These Hymns are classified thus.
Stotras, addressed by a Devotee, praising the God by perfect attributes and requesting grant of Relief/ Boons,
Slokas or verses composed by great writers of epics like Ramayana and Mahabharata, or by great poets like Kalidasa.
These slokas form a part of the narrative where the Gods are praised.
Having been revealed/written by inspiration and impelled by creative urge these slokas are powerful and they can be recited.
Then one has Parayana and Pooja.
These two are the processes through which the Slokas and stotras are recited and one has to follow laid down procedures.
Poojas are performed daily and there are standard procedures.
Another is Japa when a specific` Mantra, initiated by a Guru is chanted.
Parayana is the recital of verses from the Puranas, like the Vishnu stuthi by Prahaladha or the Vishnu Sahasranama from Mahabharatha.
These recitals follow some rules, like the one from Ramayana Sundarakanda.
Then we have the Veda Mantras like the Five Sukthas, Purusha Suktham, Narayana Suktham,Vishnu Sukhtham,Sri Suktham and Durga Suktham and of course the SriRudram.
Excepting for Parayanas and daily Poojas, protection is necessary, though procedures for daily Poojas and Parayana are available.
For reciting specific Mantras, Veda Sukthas, Sri Rudram,Lalitha and Vishnu Sahasranama one has to take adequate protection for the Limbs, Anga and for organs of action.
There are two functions for any sense organ.
Eye has the function or act of seeing, this is called Karma function and in this aspect eye is a Karmendriya.(Organ of action)
Eye, apart from seeing , also forms judgement based on the act of seeing, it acquires knowledge of what is seen.
Whether it is a Right/wrong Knowledge , correct or incorrect is a different matter.
In this function of acquiring Knowledge eyes is a Gyanendriya( Organ of Knowledge)
Mantras being the sounds grasped from Ether by Seers, are sacred and our organs should e purified and protected.
-Purified from its impurities and protected from forces that are inimical to our welfare both spiritual.
This is the reason why Anganyasa and Karanyasa are prescribed for these Mantras.
And these form an Armour .
This is the Armour of Gods
In addition to this or in some cases, in place of these, are the Bandhanas are prescribed , for example in Vishnu Sahasranama ,Lalitha Sahasranama.
These are stated before the Dhyana Slokas.
These Mantras also contain details of the Rishi who grasped the mantra, , the Devatha of the mantra, the meter in which the Prayer is to be chanted
‘Asya Shriivishhnor-Divyasahasranaama Stotra Mahaa Mantrasya
Shri Vedavyaaso Bhagavaan Rishhih
Shri Mahaavishnuh Paramaatmaa Shriimannaaraayano Devataa
Amritaam Shuudbhavo Bhaanuriti Bieejam
Devakee Nandanah Srashteti Shaktih
Udbhavah Kshobhano Deva Iti Paramo Mantrah
Shankha-Bhrinnandakii Chakriiti Keelakam
Shaarngadhanvaa Gadaadhara Ityastram
Rathaangapaani Rakshobhya Iti Netram
Trisaamaa Saamagah Saameti Kavacham
Aanandam Parabrahmeti Yonih
Rituh Sudarshanah Kaala Iti Digbandhah
Shri Vishvaruupa Iti Dhyaanam
Shri Mahaavishhnu Priityartham Sahasranaama Jape Viniyogah
Ksheerodanvath Pradese Suchimani Vilasad Saikathe Maukthikanam
Malaklupthasanastha Spatikamani Nibhai Maukthiker Mandithangah
Shubrai-Rabrai-Rathabrai Ruparivirachitai Muktha Peeyusha Varshai
Anandi Na Puniyadari Nalina Gadha Sankapanir Mukundaha…..
The mantras shall be effective when these are chanted and the appropriate mudras performed.
For more on Anaganyasa, Karanyasa, Pooja, Parayana, slokas please read my posts on these