There are two types of Sadhana (spiritual pursuits).
"The owner / master stays on the top floor of the mansion. There is a huge Alsatian dog near the entrance gate. To enter into the mansion, either we need to befriend the Alsatian dog and bring it under our control or we need to call out loudly to the master of the mansion. Unless we do one of these it will not be possible for us to meet the master. What is this Alsatian dog? It represents maya (delusion). We need to either control this maya (delusion) or we need to call out loudly to the Master (God) by chanting his name loudly.
If we chant the name of God loudly, He will “come down” from where He is currently residing. Along with the Master (God), we can easily enter the mansion. Even the Alsatian dog (maya / delusion) will not affect us in any way. Therefore, to reach God we must do Naamasmarana (chanting of the name of the Lord). Under any circumstances, be it chanting loudly outside or silently within, we need to keep God in our heart and install Him there. The human heart is the true altar of the Divine.