If the Atmakaraka is in scorpio navamsa ,one will be troubled by snakes. If 8th lord is in sarpa drekkana or 22nd drekkana is sarpa drekkana then one will be troubled by snakes.
Once Bheemasena went to the forest for hunting .There in the forest , a python [ajagar] attacked Bheema and caught him in its grip. Bheemasena did not make any attempt to release himself .Bheemasena also did not attack it back. He stood still . Because of Bheema’s hard body , python was under distress while strangling , [if you grip a hard substance and press it hard ,your hands pain ] Bheema was stronger and his body was tough ,tougher than diamond ,iron casts and indra’s vajrayudha . Then Snake [python] asked few questions to BHeemasena , if answered it offered to leave him. Bheemasena did not offer to answer him . [ one must not use Vidya to earn money or benefits , this applies to Bramhins so also to Kshatriyas ; one must not be vidyopajeevi] .Slowly Python started losing grip and tiring ,its body started to pain and wither .The snake started losing strength.Bheemasena was in deep meditation of Narayana . That was his natural charactreristic and he was not meditating to get rid of snake.
WHo was python ? Why did Bheema not Kill it ?
Once when Indra had killed a demon named Vratrasura , the sin of Bramhahatya chased him [Vratrasura was bramhin] . Fearing Bramhahatya he hid in a lotus stalk on the earth . The kingdom of Swarga was kingless ,thus devatas decided to replace Indra with another worthy person . After Long thought and discussion ,it was decided The son of king AYU , Nahusha ,who had done many yagnyas was worthy of sitting on the Indra’s throne .Thus a human king was selected to preside over the three worlds . Thus to enable him to rule over three worlds ,they bestowed him with the boon that he would get all the punya and tapasya shakti of the one whom he sees. Thus Nahusha became the King of the three worlds .
Nahusha grew in strength day by day by acquiring the punya of everyone he saw. Thus he became arrogant with excess punya and lost his balance . He then demanded union with Shachi [ the wife of earlier Indra ] as he was indra for all purpose now ,he thought he was entitled to gain Shachi as well . All the sages grew anxious at the evil thought of Nahusha , but they could not stop him from doing sin as they were all powerless , Their power to curse him was no more as their punya and shakti would be his as he sees them.
Shachi was very scared but there was none she could turn to . Indra had given her one advice before leaving the Swarga to be used in such situations. As Nahusha sent his emissary to her palace that he would arrive for her , She said she would accept only if he comes in a Palaki which is carried by Agastya and other prominent Rishis.[She knew rishis would save her]
Nahusha ordered Agastya and others to carry him on their shoulders to Shachi’s palace . Sage Brigu was always present in the Jata[hairlocks ] of Agastya . Now while carrying Agastya initiated a discussion with Nahusha ” whether Vedas are pramana [valid statements ] “
intention was , if Nahusha says yes ,then parastree sanga [ cohabitating other woman ] is prohibited in Vedas , then why was he doing such ghastly thing ? If Nahusha persists then he will be entitled to curse !!!
But Nahusha was quick to grasp this intention and thus said ” He did not consider Vedas as Valid” , Agastya persisted with argument of proving Vedas as Valid , angered Nahusha kicked the jata of Agastya . Now Bhrigu was in the jata of Agastya , and he was not yet seen by the Nahusha and his powers were intact ,thus cursed him ” that he become python ” [Those who copulate with friend’s wives or wives of elders become python in the next birth] .
Nahusha prayed Bramha for relief , thus Bramha said when he will be effectless against a human stronger than him and if he does not budge to his grip and neither answers him , then all the punya gathered by him from rishis will be transfered to him and he will be released from his curse .
Yudhisthira seeing apashakuna everywhere , enquired about Bheema , and started to look for him . There they found huge trees fallen in a arranged manner in the forest , it confirmed Bheema might have gone in that direction [ When Bhemma runs ,his mere touch of thighs towards forest trees fell them] . There Yudhisthira saw Bheema in the grip of struggling python. Yudhisthira asked python as what was his intention , it asked him few question , Yudhisthira answered them for Bheema , and Nahusha appeared in celestial form went away to Swarga.