Fully believing in the words of the goddess Durgā, Kaṁsa exhibited his familial affection for Devakī and Vasudeva by immediately releasing them from their iron shackles.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
मोचयामास निगडाद्विश्रब्धः कन्यकागिरा । देवकीं वसुदेवं च दर्शयन्नात्मसौहृदम्
mocayāmāsa nigaḍādviśrabdhaḥ kanyakāgirā | devakīṃ vasudevaṃ ca darśayannātmasauhṛdam
SB 10.4.24