Skandapurana 5.128.26

5.128.26

.. yājñavalkya uvāca .. ..
na homāṃtaṃ vinā mantraḥ sphurate pārthivottama ..
abhiṣekavidhau prokto yaḥ pūrvaṃ padmayoninā ..
tasmānnāhaṃ kariṣyāmi tava yadvai hṛdi sthitam.. 26 ..

Yājñavalkya said: / "A mantra does not take effect without concluding with an oblation, O best of kings, / as was declared anciently by the Lotus-born [Brahmā] in the rite of ablution. / Therefore, I shall not do what is in your heart."