Look at the sun. It rises every morning and sets by the evening. Sun is a shakti. And like every shakti in Creation, its time on earth (prithvilok) is bound by time; and so is our time bound, how long will we be able to experience the sun. Every shakti has a specific purpose and is sent to earth for a stipulated period of time. Sun and various shaktis of Creation are limitless in their capacity and are accessible to all the inhabitants of earth, it is upon an individual to access it while there is opportunity. If you think, ‘let me do this first, and I’ll come for that (shakti) later’, there is a strong chance that that later may never come.
For you to access the shakti of the sun, you have to take a step outside and look at the sun. If you choose to draw the curtains of your room, then sun is not going to chase you to let it endow you with its shakti… and by the time you change your mind, it may be dusk already. The desire and priority has to be your own. Unfortunately there’s only a handful who understand this aspect of sun, and even fewer who want the gyan that the sun has to offer. Most are content with a little bit of sun to keep them warm, to grow their food and to cook their meals… they don’t want more. Hence sun’s presence on earth is limited, if it stays any longer, the inhabitants of earth will not be able to bear it. But then sun is available 24×7 in suryaloka, because the shakti and beings of that loka are such.
Even Ram and Ravan were shaktis, and their time on earth too was limited. One could either be on the side of Ram and earn moksh by aiding in Hari Karya or be his enemy and earn moksh by being killed by him. What is important is to access that energy while there is time. Guru is one energy which is accessible to the shishya at all times across lifetimes but for that one has to make a Guru and become a shishya by transference of shakti till there is time and opportunity.
We will go back to the example of sun. It is clear in its path and direction. It moves in a straight line. The definition of straight line is — the shortest distance between two points. If you move in a zig-zag manner, a lot more time and energy is required, which may or may not be at your disposal. So if you consider someone as your Guru, just walk right behind him/her, in a straight line. You will reach — that is, you will imbibe his/her qualities and become him/her. There is nothing to learn or memorise in yog, it is just imbibing the qualities of your sadhya and becoming him/her — what the Vedas describe as shivohum, tat tvam asi and aham brahmasmi. But to attain this one needs to walk in a straight line with an identified purpose of life because what is there will soon be history…