Kala in context of time:
Fact is whatever we do and however we do, we need to understand one basic thing that time does not stops for anyone nor can anyone stop time. Even if we are not doing anything time is ticking on and it has been ticking on since infinity and it will keep on doing that till infinity.
Kala in context of darkness:
Another fact is that everything around us is dark indeed and it has been like that since infinity and will continue to be like that for infinity. We see an object only when that object stops the light that we are getting from the sun otherwise it's all dark. But still we see just one side that side which is visible to our eyes. For instance we see moon only because it stops the light coming from sun otherwise it is a dark object but again we see only one bright side the other side is dark, on specific days we see no moon at all. But eventually sun will also become a black hole.
In Hinduism we term both time and darkness as Shiva and refer to him by many names and one of them is 'Mahakaal'
Who is Shiva?
Although Lord Shiva is more populary known as Mahakaal as his consort is Mahakali. 'Kala' name which means 'who is time' is stated in Taittariya Aranyaka 10.18.1
As described by Sadhguru himself here:
Shiva is described as a non-being, not as a being. Shiva is not
described as light, but as darkness. Humanity has gone about
eulogizing light only because of the nature of the visual apparatus
that they carry. Otherwise, the only thing that is always, is
darkness. Light is a limited happening in the sense that any source of
light – whether a light bulb or the sun – will eventually lose its
ability to give out light. Light is not eternal. It is always a
limited possibility because it happens and it ends. Darkness is a much
bigger possibility than light. Nothing needs to burn, it is always –
it is eternal. Darkness is everywhere. It is the only thing that is