1.  To be guarded vigilantly, Prov 4:23.
2.  God desires inward truth, Psa 51:6.
3.  God looks upon, 1 Sam 16:7.
4.  God calls for heart-service, not lip-service, Mt 15:8.
5.  The heart is the cause of all our problems, and salvation begins here, Eze 36:26.