Japa Mala is sacred in itself and is made by things which denote purity, it consist of 108 beads, so the chanter keep in mind the number of rounds he or she did with mala,
As per Angira Smriti"असंख्या तु यज्जप्तं, तत्सर्व निष्फलं भवेत्" means the numberless japa done without mala is futile,
The benefits of different mala or rosary is different as per their content made, by the friction of thumb and finger a unique electric vibrations are produced which travel deep down the heart chakra and create an impact, and the wavering mind becomes still and at peace,
The middle finger has direct connect with the heart area, and it is in the heart area the sacred soul resides, to connect soul directly with the mala, it is twiddled through middle finger,
The number of beads has been designed on the basis of stars (नक्षत्र), the ancient sages discovered 27 different stars, and each start has four different phases (चरण) , finally 27 x 4 is 108 and thus 108 beads are used in japa mala, and is considered as sacred number,
So doing one circle of 108 beads is equal to the one circle of universe, by the friction between middle finger and thumb, a heavenly or sacred electrical energy is produced and rotates in a circle as we do mala japa,
Since mind is wavering and wandering, this energy brings back mind to one place and make it still, thus creating eternal calmness and peace, helping us to sync mind, body and soul,
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