Matthew 5 : 8
“Blessed are the pure in heart, for they shall see God.”
It is the inner moral purity and not ceremonial or apparent purity.It is also for having a single, undivided heart, utterly sincere in their devotion and commitment to God.
The reward is a very close and unimaginable intimacy with God. This must be the motivational force to belong to Him and Him alone.
Such commitment ensures answers to prayers!