Teaching of Sadguru and Devotional Practice for spiritual endeavours is not a strain to the Sadhaka, but to make him a realised person and make him ever happy. Sadguru puts bliss directly into your heart.
The Knowledge of the Oneness of Brahman leads you to the highest bliss. Identity of the Brahman is not possible if you view them along with their upadhis or add-ons. Eliminate the upadhis, and you find the Reality.
Don’t chase your mind. You must have complete conviction in the mind that nothing is true except the Self. Mind is the greatest bondage. If you want to be realized, you have to let go of your mind. Your mind can merge into Reality when you don’t give value to the world.