Garga Muni said: My dear Nanda Mahārāja, I am the priestly guide of the Yadu dynasty. This is known everywhere. Therefore, if I perform the purificatory process for your sons, Kaṁsa will consider Them the sons of Devakī.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
गर्ग उवाच । यदूनामहमाचार्यः ख्यातश्च भुवि सर्वतः । सुतं मया संस्कृतं ते मन्यते देवकीसुतम्
garga uvāca | yadūnāmahamācāryaḥ khyātaśca bhuvi sarvataḥ | sutaṃ mayā saṃskṛtaṃ te manyate devakīsutam
SB 10.8.7