Not everyone who says to me, 'Lord, Lord,' will enter the kingdom of heaven, but only he who does the will of my Father who is in heaven. 

                                                                    Matthew 7:21

Because these people use the name of the Lord as a banner, but they are thinking of unrighteous things.  Only those who follow the Father's will can get closer to the Kingdom of Heaven. We should pay attention to the line "do the will of my Father", which means to truly practice and apply in real life. This is the only way.

Jesus also emphasized the importance of the intention, and earlier he also emphasized that only good seeds can grow into good trees and bear good fruits.  This shows that the most important thing is the seed, which means the intention and motivation. 

The heart is the root. If the heart is not pure, the tree that grows and the fruits that it bears won’t be good.