Indriyas is a Sanskrit term. It denotes “tentacles” that we “extend” from our organs of sense and from the mind (manas) and
consciousness (buddhi) — to the objects which we perceive or think about.
Krishna presented fundamental knowledge about working with indriyas in the
Bhagavad Gita. He said about indriyas of vision, audition, smell, touch, proprioreception, and about those of the mind.
And indeed: concentration of attention on an object through any organ of sense or through the mind is very similar to extending a tentacle to that object from the body. When we switch concentration to another object, we detach our indriyas and move them to it.
In the same manner, the mind creates its own indriyas, when we think about something or someone. People with developed sensitivity can perceive other people’s indriyas that touch them. In some cases, such people can even see those indriyas and therefore can influence them.
Krishna said that man should learn is the ability to draw all his indriyas from the material world inwards, just like a tortoise retracts its paws and head into its shell. Then man should extend his indriyas into the Divine
eons in order to embrace God with them, to draw himself to Him and to merge with Him. That is, our task on the spiritual Path is to direct the indriyas of the mind and then those of the consciousness — to God in order to merge with Him eventually.
As a conclusion, it should be noted that one cannot gain the control over the indriyas without mastering first the ability to move the concentration of the consciousness between the
chakras and main meridians.