The three lines on forehead of Hindus drawn using holy ash
is known as Vibhuti. The three lines have deep symbolic meaning attached to it.
The three lines made of holy ash are usually worn by Shaiva devotees.
The three lines symbolically represent the three forms of
Shiva. The upper line represents Maheshwara; the middle line represents
Sadashiva and the lower line represents Mahadeva.
The three lines represent self, inner self and the supreme
self. Upper line represents atman (self); middle line represents
antarikshaloka (inner self) and the lower line represents Paramatman (Supreme
Self).
The three lines symbolize the three house hold fires ever to
be burning. The upper line is grahapatyagni; the middle line is dakhinagni and
the lower line is ahavaniyagni.
The three lines represent the three measures of Pranava, OM (A, U, M). The upper line represents A; the middle
line represents U and the lower line represents M.
The three lines also symbolize the three gunas. The upper
line is rajas; the middle line is sattava and the lower line is tamas.
The three lines also represent the three worlds – upper line
represents bhuloka (earth); the middle line represents antariksha (inter-sphere)
and the lower line represents dyuloka (heaven)
The three lines also represent Kriya Shakti
(action); iccha Shakti (will) and jnana Shakti (knowledge).