Aditya Hrudayam is a hymn dedicated to the Sun God found in the Yuddha Kanda of Valmiki Ramayana. It was recited by the sage Agastya to Lord Rama in the battlefield, when Lord Rama was feeling dejected, as Ravana was continuing to fight with a great deal of courage despite losing some of his key people in the war. Then, sage Agastya teaches Rama, the prayer to the Sun god (called Aditya Hrudayam) for strength and courage to defeat the enemy. This prayer is given great importance by many realized masters.
Kanchi Paramacharya is also quoted to have said that the verses from 15 to 21 (from nakshatra graha taaranam.. to ravaye lokasakshine) are special and potent words. Seshadri Swamigal is also said to have mentioned that a regular chanting of the hymn, together with Rama nama japam, is also recommended for one’s liberation. Moreover, this hymn is said to bestow purity of mind and dispassion, if chanted regularly at the dawn with the mind concentrating on the rising Sun.
The best place to look for the benefits of this hymn is the epilogue, the Phalasruthi. Here are some verses and their meaning, that describe the benefits of chanting this hymn, picked up from both the text itself as well as its epilogue.
एनमापत्सु कृच्छ्रेषु कान्तारेषु भयेषु च । कीर्तयन् पुरुषः कश्चिन्नावसीदति राघव ॥ २५ ॥
- The one who recites this hymn will be protected during the difficult times and times of fear. Those singing the glory of the Sun God will never be defeated.
पूजयस्वैनमेकाग्रो देवदेवं जगत्पतिम् । एतत् त्रिगुणितं जप्त्वा युद्धेषु विजयिष्यसि ॥ २६ ॥
- Devoting with utmost concentration on the Sun god, if one recites this hymn three times a day, one will be victorious in battles.
आदित्यहृदयं पुण्यं सर्वशत्रुविनाशनम् । जयावहं जपं नित्यम् अक्षयं परमं शिवम् ॥ ४ ॥
- This hymn is holy and can destroy all the enemies. By chanting this daily, one can bring victory to oneself all the time without much effort and achieve unending felicity.
सर्वमङ्गलमाङ्गल्यं सर्वपापप्रणाशनम् । चिन्ताशोकप्रशमनम् आयुर्वर्धनमुत्तमम् ॥ ५ ॥
- This hymn is great and auspicious. It brings prosperity, destroys all sins, alleviates worry and sorrows, bestows wellbeing and longevity.
Apart from the spiritual benefits, this hymn also helps one overcome mental depression, cure diseases, win over enemies etc.
The full text of the hymn can be found at: Ādityahṛdayam – Wikipedia