As mentioned in verse 26, chapter 10 of Shrimad Bhaguad Geeta, Lord Krishna himself says that among trees He is Peepal. Therefore, devout Hindus get ready even to lay down their lives happily in defence of a Peepal tree. So the Peeped tree is considered as the abode of Lord Vishnu.
According to verse 41-44 in Skandapurana chapter 247, Lord Vishnu lives in the roots of Peepel, Keshav in trunk, Narayan in branches, Lord Hari in the leaves, and all gods in the fruits of PeepaL This tree is concrete and living form of Shri Vishnu. Persons of great souls serve its pious roots. Its shelter, enriched with virtues and fulfilling all wishes, eliminates thousands of sins of men.
Scientific research has revealed that among tress, Peepal is the only tree that produces oxygen in abundant quantity day and night, which is so essential for life. Its shade is warm in winter and cool in summer. Peepal provides life sustaining oxygen, which proves it to be a life-sustainer. Continuous research has also proved that the sound and interacting flow of wind, with Peepal leaves, slowly but surely kills infectious bacteria as well.
According to the books of Ayurveda, Peepal leaves, fruits and bark are killers of diseases. It is used in the treatment of a number of diseases, such as blood impurities, cough, bile, gastric, inflammation, distaste, food-poisoning, alternate day fever, hiccups, burning in throat, nasal disorders, worms, leprosy, skin, wounds, wounds caused by burning, bagi etc.