Kansa had known that during the battle between the gods and demons he was the demon Kalnemi, and he was killed by Lord Vishnu. So fearing Lord Vishnu rallying with Yaduvanshis, Kansa cultivated high degree of hostility towards them. He captured even his father Ugrasen and put him in the prison. Now the reign of the kingdom was entirely in his hands. Kansa was himself very strong and also had the assistance of his father-in-law, Jarasandh. Formidable demon like Pralamb, Baka, Chanur, Trinavart, Aghasur, Mushtik, Arisht, Dvivid, Pootana, Kashi and Dhenuk were his courtiers. As a result of Kansa atrocities en mass exodus of Yaduvanshis from Mathura followed. These Yaduvanshis left Mathura and settled in regions like Kuru, Panchal etc. Still some of them accepted to serve Kansa, but only superficially.
When all pervasive Lord saw that Yaduvanshis were being tortured without reason, He transferred his glory in Vasudev. Through Vasudev, Devaki received that brilliant part of the lord. On the other hand, Kansa also came to know about Devaki‘s eighth issue. Since, then his hostility surged unprecidently and he began to wait for the birth of Devaki’s eight son very anxiously. All it means to say that Kansa mind reflected on God every moment day in and day out.