[Luk 6:45 KJV] 45 A good man out of the good treasure of his heart bringeth forth that which is good; and an evil man out of the evil treasure of his heart bringeth forth that which is evil: for of the abundance of the heart his mouth speaketh.

[Psa 37:30 KJV] 30 The mouth of the righteous speaketh wisdom, and his tongue talketh of judgment.

[Pro 10:20 KJV] 20 The tongue of the just [is as] choice silver: the heart of the wicked [is] little worth.

[Pro 12:6, 17-19 KJV] 6 The words of the wicked [are] to lie in wait for blood: but the mouth of the upright shall deliver them. ... 17 [He that] speaketh truth sheweth forth righteousness: but a false witness deceit. 18 There is that speaketh like the piercings of a sword: but the tongue of the wise [is] health. 19 The lip of truth shall be established for ever: but a lying tongue [is] but for a moment.

[Pro 15:4, 23 KJV] 4 A wholesome tongue [is] a tree of life: but perverseness therein [is] a breach in the spirit. ... 23 A man hath joy by the answer of his mouth: and a word [spoken] in due season, how good [is it]!

[Deu 5:29 KJV] 29 O that there were such an heart in them, that they would fear me, and keep all my commandments always, that it might be well with them, and with their children for ever!

[Deu 6:5-6 KJV] 5 And thou shalt love the LORD thy God with all thine heart, and with all thy soul, and with all thy might. 6 And these words, which I command thee this day, shall be in thine heart:

[1Sa 16:7 KJV] 7 But the LORD said unto Samuel, Look not on his countenance, or on the height of his stature; because I have refused him: for [the LORD seeth] not as man seeth; for man looketh on the outward appearance, but the LORD looketh on the heart.

[1Ch 28:9 KJV] 9 And thou, Solomon my son, know thou the God of thy father, and serve him with a perfect heart and with a willing mind: for the LORD searcheth all hearts, and understandeth all the imaginations of the thoughts: if thou seek him, he will be found of thee; but if thou forsake him, he will cast thee off for ever.

[2Co 12:14 KJV] 14 Behold, the third time I am ready to come to you; and I will not be burdensome to you: for I seek not yours, but you: for the children ought not to lay up for the parents, but the parents for the children.

[Psa 51:10 KJV] 10 Create in me a clean heart, O God; and renew a right spirit within me.

[Jer 17:9-10 KJV] 9 The heart [is] deceitful above all [things], and desperately wicked: who can know it? 10 I the LORD search the heart, [I] try the reins, even to give every man according to his ways, [and] according to the fruit of his doings.

[Mat 5:8 KJV] 8 Blessed [are] the pure in heart: for they shall see God.

[Mat 12:33, 36-37 KJV] 33 Either make the tree good, and his fruit good; or else make the tree corrupt, and his fruit corrupt: for the tree is known by [his] fruit. ... 36 But I say unto you, That every idle word that men shall speak, they shall give account thereof in the day of judgment. 37 For by thy words thou shalt be justified, and by thy words thou shalt be condemned.

[Mat 15:18-20 KJV] 18 But those things which proceed out of the mouth come forth from the heart; and they defile the man. 19 For out of the heart proceed evil thoughts, murders, adulteries, fornications, thefts, false witness, blasphemies: 20 These are [the things] which defile a man: but to eat with unwashen hands defileth not a man.

[Mat 23:26 KJV] 26 [Thou] blind Pharisee, cleanse first that [which is] within the cup and platter, that the outside of them may be clean also.

[Heb 3:8 KJV] 8 Harden not your hearts, as in the provocation, in the day of temptation in the wilderness: