What is Som, referred to in the Rig Veda?

There is fire element in the base chakra. Do you know, whenever you are eating food, the brain sends some signals and enzymes get created in the body? Do you know about it? Soma is that cooling fluid which is generated from top chakra. Life is a combination of Soma and Fire, the cool and the hot. There is the fire element in the Mooladhara Chakra, Swadisthana Chakra, Manipura Chakra and sometimes in the Anahata chakra also.
Sometimes we say that I have fire burning in my heart', isn’t it? So, in these 4 lower chakra’s the fire element is dominant. And the upper three chakras have the cooling element dominant. If you see, it is said that the third eye which is related to anger, has fire element dominating. We never say that we have feeling of fire in our throats. When we feel sad or very grateful the throat gets choked. So Somras is the fluid which is released from the brain and flows downward in the body, and the fire element rises upwards from the lower chakras. They meet at the Anahata (Heart) chakra and that is what is called Agnistoma. This is what is the essence of the Vedas - the technique of meditation that creates equilibrium between the hot and the cold, which creates a positive balance.

Do You Have To Be Thankful And Feel Obliged?

When you are on a spiritual path, you are not thankful or obliged to anybody. In the Gita, Krishna says, "He is dear to Me who neither goes on thanking people nor hates anyone (Na abhinandati na dveshthi)." Thanking and feeling obliged indicates that you believe in some one else's existence rather than in the Divine who is ruling everything. When you feel obliged, then you are not honoring the principles of karma or the divine plan.
Appreciate people for what they are, do not thank them for what they do. Otherwise your thankfulness is centered around ego. You are grateful, but not for an act. You are grateful for what is. As every individual is nothing but a puppet of the ONE, thanking and being obliged is simply an exhibition of ignorance. Everything is ruled, controlled and managed by one Divinity, that consciousness has to shine forth in every act of yours; you do not have to make a mood of it.
When you have a total sense of belonging, then gratefulness does not become an obligation. Such gratefulness is for the Divine only, which enhances strength.