Kabir is sure that our saayee or god is within ourselves and exhorts us to wake up to this truth "जाग सकै तो जाग" (if you can wake up -to this truth, that is - please do.) is the simple and straightforward meaning
Sangom Ji,
Here we go. Let us take that doha of Kabir to mean the way you said, 'If you
can, wake up to the truth'. I would simply say, one CANNOT.
If so, we wouldn't be born. We are born of karma, meaning, our body organs (sense, action, mind) are all dabbed in karma, that blocks the Luminous, Self-Knowing Atma. Acc. to Upanishads, Our true self is like the Lustrous Gem, but pathetically dusty.
We should clear ourselves off of this karma (that is dispersed in every sense-organ and mind like the 'oil in the seed').
This is no "belief", this is just "common-sense" , Else, why would anyone be born, if they
all have known or realized the TRUTH? [Renuka, simply referred this COMMON-SENSE as Intuition]
Even somewhat-balanced people like us, experience many instances of anger or love or passion, our intellect gets completely blocked by a dark net! and we wouldn't want to go farther than those emotions, and evaluate the situation. After a lapse of that moment, we would feel disgusted by such obscurity of thought. So, only various experiences, various births, various roles, we should take to learn and rid of the VEIL of karma. Our mind is like the dusty mirror. Unless we clean it off with Cold Vinegar, we can't see the reflection of our True Self. Acc. to Upanishads, Our true self is like the Lustrous Gem buried inside the 'greasy' dust of Karma.
If we are at a better level of Jnana, (spread over the body, organs, mind) we get an appropriate birth (With the grace of the Creator) and get access to the right knowledge. As our worst part of karma has been cleared to some extent, the Self-Luminous Atma (dharmi-jnana), through the right Intellect/senses (Dharma-jnana), is able to immediately cling to or get attracted to the TRUTH/FACT.
Whereas, There exists NithyaSuris, the great MahAtmAs, who never have incurred any karma. Those holy souls, assist in the emancipation of the souls/Jivas, by taking birth as sages or some acharyas and revealing the right knowledge through srutis and other authoritative texts. They dont act in any self-inteterst nor for any benefit or glory. Unless our external knowledge (dharma jnana) has expanded to a required level, Our Self cannot grasp or see the TRUTH.
Such expansion, is not taking a dip in the ganges or wearing Rose scent. One should be prepared to tune their senses/mind towards the right goal of Knowing the Inner Self (self and ParamAtma).