In Sanatan Hindu religion, Tulsi plant is worshiped in every house. There are religious as well as scientific reasons behind this. Tulsi is a very positive plant. It is said that by planting and worshiping the Tulsi plant in the house, many types of Vaastu defects and negativity are removed from the house. Also, the blessings of Goddess Lakshmi always remain. Some volatile oils are found in basil leaves, which dissolve when they come in contact with air and purify the air. Medicinal properties are also found in the holy basil plant. Regular consumption of its leaves greatly increases the immunity.

There is a legendary story behind the birth of Tulsi. Once, Lord Shiva’s third eye was opened after he became enraged with Demigod Indra. Guru Brahaspati apologized to Lord Shiva and urged him to forgive Indra. The fire that was born upon Lord Shiva’s third eye opening was then released into the sea water to protect the universe from its wrath. From this great radiant flame which was emanated from Lord Shiva, a child was born who was very bright and powerful. Because of being born in water, he was named Jalandhar. This kid grew up to be the formidable or horrifying demon king.

Tulsi’s first birth was as Vrinda. A girl was born to Mathura’s king, Demon Kalanemi.

Kalanemi along with his wife named her Vrinda. She grew up worshipping Lord Vishnu and became a devotee. Vrinda married Jalandhar when she became an adult. Vrinda was a great devotee of God and a devoted woman. Whenever Jalandhar went to war, Vrinda used to meditate on God to protect her husband and Jalandhar remained safe in any war due to the strength of a devoted woman.

Once Jalandhar fought with the demigods along with a huge army of demons to get the supremacy of heaven. Under his leadership, the demons defeated the demigods and the demons ruled over heaven. The gods ran away to Guru Brahaspati. At the behest of Brahaspati, the gods took refuge in Lord Vishnu. Hearing the prayers of the gods, Lord Vishnu went to fight Jalandhar to help them. But Lord Vishnu could not defeat him since he was born from the glory of Lord Shiva and asked him to ask for a boon. Jalandhar cunningly requested Lord Vishnu to stay in his palace along with Goddess Lakshmi, which Lord Vishnu could not refuse, thus Jalandhar obtained protection from Lord Vishnu also.

After this the gods along with Guru Brahaspati went to seek refuge in Lord Shiva. To help the gods, Lord Shiva went to fight Jalandhar but even Lord Shiva could not defeat him. Then Lord Vishnu approached Lord Shiva and said, 'O God, the reason why you are not able to defeat Jalandhar is that firstly he is born out of your own power and secondly he is married to Vrinda - a pure and devoted wife. You fight with Jalandhar and I will try to divert Vrinda's attention because killing Jalandhar is necessary for the welfare of the universe.'

Saying this, Lord Vishnu took the form of Jalandhar and reached his palace, then Vrinda, thinking that her husband had come, left her penance and started serving him. Here in the war, Lord Shiva killed Jalandhar. As soon as the messengers came to inform Vrinda after Jalandhar was killed, Vrinda realized that she had been tricked.

Then she asked Lord Vishnu to come in his real form and cursed him to turn into a stone and herself got ready to burn in the fire along with her husband. But then all the Gods and Goddesses reached there and requested Vrinda to free Lord Vishnu from the curse, accepting which she forgave him but herself got burnt in the fire. Soon after, from the ashes a plant was born which was called Tulsi. Tulsi being a faithful and virtuous wife made a big impact on Lord Vishnu.

The tradition of Tulsi marriage started with the same stone form of Lord Vishnu i.e. Shaligram. Even today, the festival of Tulsi Vivah is celebrated with great pomp every year on the Ekadashi date of Shukla Paksha of Kartik month. Wherever Tulsi is worshipped, the blessings of Lakshmi and Narayana always remain there. Tulsi is very dear to Lord Vishnu and his worship is considered incomplete without Tulsi.