God Shanidev is associated with the planet saturn,Surya (son of Brahma) and Sandna (the daugther of Daksha Prajapati) are the parents of Shri Shanaishwar.
Shani Shingnapur, an important Shrine for Lord Shani, called Shingnapur is located between Shirdi and Ahmadnagar. The deity here is self emerged from earth in form of a Black Stone,that is "Swayambhu".
This Swayumbhu "Shanaishwar" is in existence at least since the Kaliyuga. One day two shepards (uncle and his nephew) found a "Black Stone" in the flowing water.
When they touched the stone with a pointed rod the stone began to bleed. The On that night Lord shanaishwar appeared in the dream of the shepherd and disclosed his identity.
He revealed him that he is Shanaishwar himself in the form of the swayambhu black stone. Soon, the villagers constructed the temple of "Shanaishwar".
As per the directions of Shanaishwar, there are no doors etc. to any house or shops, in Shingnapur and still there are no robberies, till today. It is proved that the robbers are severly punished by "Shanaishwar".
Shanaishwar is both, a giver and also a destroyer. A person who worships, Shani, will be blessed highly. Shani, the Saturn is a planet and also the god for the Hindus.
It has black colour and is ferocious in nature. There are many temples of Shani in India where special prayers and worships are offered on Saturdays.
Shani is considered to be the monitor of business pertaining to iron, oil and black coloured commodities. The reason for all mishaps, is the effect of Shani.
To protect from the annoyance of Shani, the worship of Shani or Hanumanji is recommended.
Birth of Shani
It is said that Surya Dev was initially married to Saranyu, but because of his unbearable heat and brightness, she left him and went away for penance leaving her shadow Chhaya behind.
Shani Dev is the son of Surya Dev and Chhaya, while his mother was going through severe penance. Lord Shiva has therefore, blessed Shani Dev with darkness symbolizing the power of extreme penance that he possesses.
Surya Dev or Sun God had two sons, Yama and Shani. His mother was Chhaya and hence is also known as Chhayaputra. Shani Dev represents the planet Saturn and is the lord of Saturdays.
His elder brother Yama is also known as God of death. While Yama, gives the results of one's deeds after death, Shani is known to give one the fruits of his deeds in his present life itself.
He also had two sisters Yamuna Devi and Putri Bhadra. His other two brothers are Vaivastahva Manu and Manu. When Shani was born, the sun went into an eclipse.
This denotes the impact of Shani on the Hindu astrology. Lord shani was born on Vaishak Vadya Chaturdasi Amavasya; which is observed as Shani Amavasya or Shani Jayanti.
God Shani and Hanuman
Shani was overambitious for attaining immortality. Hence the demon king Ravana invaded over Lord Shani's territory and he arrested God Shani.
As per the rules of lord Brahma, Lord Shani remained arrested till Hanumanji relieved him. Ravana had ignited tail of Hanumanji who, with his burning tail, set Lanka on fire.
While doing this he found Lord Shani arrested in the basement of Ravana's palace. Lord Shani requested Hanumanji to relieve him and he was set free. In response God Shani blessed that he may not trouble devotees of Lord Hanuman.
Shani and black dogs
It is believed since ancient times that God Shani favours them who offer food to black dogs and those people are relieved from the ill effects of Shani.
As driven by astrological prescriptions, several people feed black dogs and some people also tame a black dog in the house.
It is a time period of seven and half years when planet shani enters our 'rashi'. It remains two and half year in the previous rashi, two and half years in our our rashi and two and half years in the next rashi.
As per the Vedic astrology, sade-sati is considered to be a most troublesome time period of one's life. A person may face a lot of failures, accidents, health and financial problems.
In some cases God Shani may favour some people as per the influence of other stars.
Lord Shiva was respected as guru by God Shani. At the same time God Shiva happens to be Shani's brother-in-law, since Shiva got married to Goddess Kali. He also represents Lord Shiva's Vairagya principle.
When Chhaya, the mother of God Shani was carrying Shani in her womb, she was paying to Lord Shiva and was highly devoted to the penance of Lord Shiva.
During her seep meditations she never bothered to intake any food. This had such a massive effect on the child in her womb, that Shani was born with dark skin.