Skandapurana 16.83.42

16.83.42

śāstroktaṃ mantrasaṃyuktaṃ hotavyaṃ pāyasaṃ tataḥ..
tataḥ khaḍgaṃ tu saṃsnāpya paṃcāmṛtarasena vai..
pūjayedvividhaiḥ puṣpairmaṃtrapūrvaṃ dvijottamaiḥ..42..

Then sweet milk-rice, consecrated with mantras prescribed by scripture, should be offered into the fire; / then, having bathed the sword with the liquid of the five nectars, / he should worship it with various flowers, preceded by mantras, through the best of the twice-born.