Agni is both the sacred fireplace and the deity of that fireplace who transmits oblations to another deities. So, this mantra is recited when invoking the deity Agni in the shape of fireplace as witness to your vow. The Tantrasara describes her iconography: Bagalamukhi sits in the golden throne from https://lifewebdirectory.com/listings13297600/beej-mantra-can-be-fun-for-anyone