।।। त्रिमुखश्चैव रुद्राक्षो अप्वग्नित्रयस्वरूपकः तद्धारणाच्च हुतभुक् तस्य तुष्यति नित्यशः ।।
श्रीमद्देवीभागवतम् अ. ७, श्लो. २६

Three Mukhi Rudraksha is a form of all three types of fire. The wearer is blessed by Lord Agni.

Shrimaddevibhagavatam, Chapter. 7, Shloka. 26

Essence of Three Mukhi Rudraksha :

The Three mukhi Rudraksha is blessed by Lord Agni.

The 3 Mukhi Rudraksha is blessed by Agni (fire). He is the three faced Rig Vedic deity who is fiery and powerful. He is addressed as Mahajwalaa and Saptajivha (The one with seven tongues). Agni Dev is the deity that manifests in the fiery heat of the sun, in the lightning strike and in households as fire for cooking. Anything that touches him is reduced to ashes.

It is said to be good for boosting your energy levels, overcoming laziness and improving blood circulation. It is believed to make the wearer fearless, courageous and enhances self-esteem. It helps in subduing the negative effects of Mars. It provides a protective shield to the children.