Sun in 3rd house.

So, lets see what Sun can do in 3rd house without any conjunction or aspect from any other planet. 1st lets see what these 2 things represent -

Sun represents King, Government, Father, Authority, Career, Top Positions, Ego, Self Esteem etc.

3rd house - It is house of your communication skills, neighbours, short distance travels, younger siblings, marketing, announcements, collecting information, hobbies and skills, self-efforts, business, courage etc.

So, when Sun comes into 3rd house, it makes a person highly courageous and at times audacious. I mean there is a difference between Courage and Audacity, in earlier part of life, this person is more audacious than courageous. But as 3rd house is one of Upachaya Houses, house and planet sitting in this house improves with time and gives good results after mid 30s.

As Sun burns the house it sits in, while sitting in 3rd house of younger siblings, it either doesn't let you reap any benefit from younger sibling or there may be a situation where you might not have any younger siblings.

These people get their authority or recognition in life through their communications an self efforts. It is better for them to have their own work as Sun burns the possibility of working with groups due to ego conflicts. The day they have their own work, the same day they will start feeling confident. They need to be careful with their communications as it can lead to ego battles. They will realize their true potential only in 30s due to Upachaya Nature of 3rd house. 

All in all, a very good position for Sun, specially after age of mid 30s.

Thanks,

Swami Premanand Bharti