Mantras are a very powerful combination of words that has the power to create desired results when chanted with pure and focused intentions. I am writing this from my own experience since I did Mantra Meditation in the year 2017 for 3 months. The entire universe is composed of sounds that have vibrations and resonate at a certain frequency. A normal human being cannot hear sounds that can be heard in a trance state or a state where you are sleepy but your mind is fully awake. In that state of mind, your mind can connect directly with God and the sounds which make the entire universe.