Watch over your heart.
Proverbs 4:20-23 (NASB) reads:
20 My son, give attention to my words; Incline your ear to my sayings.
21 Do not let them depart from your sight; Keep them in the midst of your heart.
22 For they are life to those who find them And health to all their body.
23 Watch over your heart with all diligence, For from it flow the springs of life.
Matthew 5:8 (NASB) reads:
8 “Blessed are the pure in heart, for they shall see God.
How do we develop a pure heart?
1 John 3:3 reads:
3 And everyone who has this hope fixed on Him (JESUS CHRIST) purifies himself, just as He (JESUS CHRIST) is pure.
2 Corinthians 3:3 (NKJV) reads:
3 clearly you are an epistle of Christ, ministered by us, written not with ink but by the Spirit of the living God, not on tablets of stone but on tablets of flesh, that is, of the heart.
2 Corinthians 3:4-6 (NASB) reads:
4 Such confidence we have through Christ toward God.
5 Not that we are adequate in ourselves to consider anything as coming from ourselves, but our adequacy is from God,
6 who also made us adequate as servants (ministers) of a new covenant, not of the letter but of the Spirit; for the letter kills, but the Spirit gives life.