Blessed are the pure in heart, for they shall see God.
The reward for being pure in heart is to see God. God is our reward. No reward is greater than God Himself. We gain this reward by being strict, righteous, with ourselves, by being merciful toward others, and by being pure in heart toward God.
To be pure in heart is to be single in purpose, to have the single goal of accomplishing God’s will for God’s glory (1 Cor. 10:31). This is for the kingdom of the heavens. Our spirit is the organ to receive Christ (John 1:12; 3:6), whereas our heart is the ground where Christ as the seed of life grows (13:19). For the kingdom of the heavens we need to be poor in spirit, empty in our spirit, that we may receive Christ. We also need to be pure in heart, single in our heart, that Christ may grow in us without frustration.