The mind is like water. It does not stay in one place. Just like water flows downwards, the mind flows towards the descending level of sins. Great effort has to be made to direct and bring water upwards. Similarly, we have to make special efforts to concentrate the mind on God. In order to bring water upwards, we may need to use a machine/ pump. Likewise, we need a divine power such as a mantra to send the mind to another level and concentrate on God.
Our mind is easily engrossed on anything it finds interesting. Until a human gains happiness in the material objects in this world, one will remain trapped in it. Eventually, one will realise that: the world is meaningless. It is the cause of our attachments and therefore sorrows.
The short-lived happiness gained from the material world is an illusion. True happiness lies in uniting with the creator of this world. God is the ocean of bliss. He is the abode of happiness. An individual should concentrate the mind on Him.
However, the mind cannot concentrate on God until one does not develop love in the heart for Him. It is not possible to develop love for God until we are filled with vicious and impure thoughts. One can get rid of sins through chanting God’s name. Hence one should sing/chant God’s name with full faith.