The first purpose of the Somayag is that it benefits the environment. There are six seasons as mentioned in The Vedas, and the 6 Pravargyas that are happening in the Somayag correlate to the six seasons of the environment.
Soma is said to be the king of all herbs in the Vedas. That’s why this Soma juice is offered in the Somayag, which will further nourish all the environment and later on come in the form of rains and ultimately nourish all the herbs on the planet and all humans.
Holy scripture says that through Yajnyas rain comes in and through rain, food grain comes in. This means that Soma ultimately helps all the Earth’s biosphere, which ultimately helps the rain, and ultimately helps grow the food crops which give us energy in order to survive in this world. That is why Somayag needs to be performed everywhere. This is the main purpose of Somayag.
The energy, the sound created during the Somayag, resonates with us. It acts as an amplified effect which ultimately affects our mind, which purifies our mind. That is also one effect of Somayag.
On the first day of Somayag, the Yajaman and the Yajaman’s wife [Achal Apte and his wife Bhakti Apte] take a vow. There is a shloka which says that the Yajaman is the fire, and fire is the Yajaman. This means that the Yajaman becomes the fire. The fire cannot take baths; we shall not extinguish the fire through water. That’s why the Yajaman shall not take a bath during the period of Somayag, as he himself is a form of fire. On the 5th day they give up the vow and on that day they can take a bath in the river. For example, when we want to give any shape to any metal, say, for example, gold, we have to heat up the gold, and we have to give it one specific shape. When the shape has been completed, we immerse the gold into water, it solidifies, and it gets that exact shape. In the same way, the Yajaman becomes fire; during the first day he takes a vow. He becomes the fire, and on the 5th day he takes a bath in the river. It just denotes that he becomes the divine.
The Yajaman also is the representative of all the people who are a part of the Yajnya. On the first day he is a representative of all the people who are part of the Yajnya, and on the last day he is a representative and a part of everybody, and on the 5th day, he gives up everything, whatever he has, to everybody. He is fasting during the period of Somayag.
The minimum period for Vedic studies is 6 years to 7 years. For a complete study, it is almost 14 years.
In order to take the vow of Tretagni, a wife is required. Only husband and wife together can take this vow. Bhakti, Achal’s wife, plays an important role in order to do any procedure. If the wife is not present, if Bhakti is not present, the Yajaman doesn’t have the right or cannot perform any of the procedures. The mantras which the wife has to know, which need to be chanted during the Somayag, for that one year of study is required.
The Yajaman needs to be married and needs to have a child, in order to serve the Tretagni. The ultimate purpose of having a son or a daughter is to secure that even the next generation will go on continuing the tradition, the things which the parents are following. Only then, later on, they can take the vow of Tretagni fire. The person who has Tretagni only can perform Somayag.