The Heart

The heart is deceitful above all things
    and beyond cure.
    Who can understand it?

10 “I the Lord search the heart
    and examine the mind,
to reward each person according to their conduct,
    according to what their deeds deserve.”

Warning Against Unbelief

So, as the Holy Spirit says:

“Today, if you hear his voice,
    do not harden your hearts
as you did in the rebellion,
    during the time of testing in the wilderness,
where your ancestors tested and tried me,
    though for forty years they saw what I did.
10 That is why I was angry with that generation;
    I said, ‘Their hearts are always going astray,
    and they have not known my ways.’
11 So I declared on oath in my anger,
    ‘They shall never enter my rest.’ [a]

12 See to it, brothers and sisters, that none of you has a sinful, unbelieving heart that turns away from the living God. 13 But encourage one another daily, as long as it is called “Today,” so that none of you may be hardened by sin’s deceitfulness. 14 We have come to share in Christ, if indeed we hold our original conviction firmly to the very end. 15 As has just been said:

“Today, if you hear his voice,
    do not harden your hearts
    as you did in the rebellion.”[b]

16 Who were they who heard and rebelled? Were they not all those Moses led out of Egypt? 17 And with whom was he angry for forty years? Was it not with those who sinned, whose bodies perished in the wilderness? 18 And to whom did God swear that they would never enter his rest if not to those who disobeyed? 19 So we see that they were not able to enter, because of their unbelief.

20 But store up for yourselves treasures in heaven, where moths and vermin do not destroy, and where thieves do not break in and steal. 21 For where your treasure is, there your heart will be also.

45 A good man brings good things out of the good stored up in his heart, and an evil man brings evil things out of the evil stored up in his heart. For the mouth speaks what the heart is full of.

The Greatest Commandment

28 One of the teachers of the law came and heard them debating. Noticing that Jesus had given them a good answer, he asked him, “Of all the commandments, which is the most important?”

29 “The most important one,” answered Jesus, “is this: ‘Hear, O Israel: The Lord our God, the Lord is one.[a] 30 Love the Lord your God with all your heart and with all your soul and with all your mind and with all your strength.’[b] 31 The second is this: ‘Love your neighbor as yourself.’[c] There is no commandment greater than these.”