Is it to wake up the Lord? But the Lord never sleeps. Is it to let the Lord know we have come? He does not need to be told, as He is all knowing. Is it a form of seeking permission to enter His precinct? It is a homecoming and therefore entry needs no permission. The Lord welcomes us at all times. Then why do we ring the bell?
The ringing of the bell produces what is regarded as an auspicious sound. It produces the sound Om, the universal name of the Lord. There should be auspiciousness within and without, to gain the vision of the Lord who is all-auspiciousness.
Even while doing the ritualistic aarati, we ring the bell. It is sometimes accompanied by the auspicious sounds of the conch (more) and other musical instruments. An added significance of ringing the bell, conch and other instruments is that they help drowned any inauspicious or irrelevant noises and comments that might disturb or distract the worshippers in their devotional ardour, concentration and inner peace.
As we start the daily ritualistic worship (pooja) we ring the
Kurve ghantaaravam tatra
I ring this bell indicating
the invocation of divinity,
So that virtuous and noble forces
enter (my home and heart);
and the demonic and evil forces
from within and without, depart.
People who are visiting the temple should and will Ring the bell before entering the inner sanctum (Garbhagudi or Garbha Gruha or womb-chamber) where the main idol is placed. According to Agama Sastra, the bell is used to give sound for keeping evil forces away and the ring of the bell is pleasant to God. However, the scientific reason behind bells is that their ring clears our mind and helps us stay sharp and keep our full concentration on devotional purpose. These bells are made in such a way that when they produce a sound it creates a unity in the Left and Right parts of our brains. The moment we ring the bell, it produces a sharp and enduring sound which lasts for minimum of 7 seconds in echo mode. The duration of echo is good enough to activate all the seven healing centres in our body. This results in emptying our brain from all negative thoughts.