rājavidyā rājaguhyayoga - Verse śloka 23
śloka 23
ye'pyanyadevatā bhaktā yajante śraddhayānvitāḥ |
te'pi māmeva kaunteya yajantyavidhipūrvakam ||9-23||
Translation
O Kaunteya! Those devotees endowed with faith who worship other deities—they too worship Me alone, though not according to the prescribed method.