[2Ch 12:14 KJV] 14 And he did evil, because he prepared not his heart to seek the LORD.

[Pro 4:23 KJV] 23 Keep thy heart with all diligence; for out of it [are] the issues of life.

[Ecc 5:6 KJV] 6 Suffer not thy mouth to cause thy flesh to sin; neither say thou before the angel, that it [was] an error: wherefore should God be angry at thy voice, and destroy the work of thine hands?

[Isa 1:18 KJV] 18 Come now, and let us reason together, saith the LORD: though your sins be as scarlet, they shall be as white as snow; though they be red like crimson, they shall be as wool.

[Isa 44:20 KJV] 20 He feedeth on ashes: a deceived heart hath turned him aside, that he cannot deliver his soul, nor say, [Is there] not a lie in my right hand?

[Jer 17:9 KJV] 9 The heart [is] deceitful above all [things], and desperately wicked: who can know it?

[Eze 20:16 KJV] 16 Because they despised my judgments, and walked not in my statutes, but polluted my sabbaths: for their heart went after their idols.

[Mat 12:31, 33-35 KJV] 31 Wherefore I say unto you, All manner of sin and blasphemy shall be forgiven unto men: but the blasphemy [against] the [Holy] Ghost shall not be forgiven unto men. ... 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. 34 O generation of vipers, how can ye, being evil, speak good things? for out of the abundance of the heart the mouth speaketh. 35 A good man out of the good treasure of the heart bringeth forth good things: and an evil man out of the evil treasure bringeth forth evil things.

[Mat 15:2-20 KJV] 2 Why do thy disciples transgress the tradition of the elders? for they wash not their hands when they eat bread. 3 But he answered and said unto them, Why do ye also transgress the commandment of God by your tradition? 4 For God commanded, saying, Honour thy father and mother: and, He that curseth father or mother, let him die the death. 5 But ye say, Whosoever shall say to [his] father or [his] mother, [It is] a gift, by whatsoever thou mightest be profited by me; 6 And honour not his father or his mother, [he shall be free]. Thus have ye made the commandment of God of none effect by your tradition. 7 [Ye] hypocrites, well did Esaias prophesy of you, saying, 8 This people draweth nigh unto me with their mouth, and honoureth me with [their] lips; but their heart is far from me. 9 But in vain they do worship me, teaching [for] doctrines the commandments of men. 10 And he called the multitude, and said unto them, Hear, and understand: 11 Not that which goeth into the mouth defileth a man; but that which cometh out of the mouth, this defileth a man. 12 Then came his disciples, and said unto him, Knowest thou that the Pharisees were offended, after they heard this saying? 13 But he answered and said, Every plant, which my heavenly Father hath not planted, shall be rooted up. 14 Let them alone: they be blind leaders of the blind. And if the blind lead the blind, both shall fall into the ditch. 15 Then answered Peter and said unto him, Declare unto us this parable. 16 And Jesus said, Are ye also yet without understanding? 17 Do not ye yet understand, that whatsoever entereth in at the mouth goeth into the belly, and is cast out into the draught? 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.

[1Co 5:6 KJV] 6 Your glorying [is] not good. Know ye not that a little leaven leaveneth the whole lump?

[Eph 2:1-5 KJV] 1 And you [hath he quickened], who were dead in trespasses and sins; 2 Wherein in time past ye walked according to the course of this world, according to the prince of the power of the air, the spirit that now worketh in the children of disobedience: 3 Among whom also we all had our conversation in times past in the lusts of our flesh, fulfilling the desires of the flesh and of the mind; and were by nature the children of wrath, even as others. 4 But God, who is rich in mercy, for his great love wherewith he loved us, 5 Even when we were dead in sins, hath quickened us together with Christ, (by grace ye are saved;)

[Heb 3:13 KJV] 13 But exhort one another daily, while it is called To day; lest any of you be hardened through the deceitfulness of sin.

[Heb 12:5 KJV] 5 And ye have forgotten the exhortation which speaketh unto you as unto children, My son, despise not thou the chastening of the Lord, nor faint when thou art rebuked of him:

[Jas 1:14-15 KJV] 14 But every man is tempted, when he is drawn away of his own lust, and enticed. 15 Then when lust hath conceived, it bringeth forth sin: and sin, when it is finished, bringeth forth death.

[Jas 2:10-11 KJV] 10 For whosoever shall keep the whole law, and yet offend in one [point], he is guilty of all. 11 For he that said, Do not commit adultery, said also, Do not kill. Now if thou commit no adultery, yet if thou kill, thou art become a transgressor of the law.

[Jas 4:1-3, 17 KJV] 1 From whence [come] wars and fightings among you? [come they] not hence, [even] of your lusts that war in your members? 2 Ye lust, and have not: ye kill, and desire to have, and cannot obtain: ye fight and war, yet ye have not, because ye ask not. 3 Ye ask, and receive not, because ye ask amiss, that ye may consume [it] upon your lusts. ... 17 Therefore to him that knoweth to do good, and doeth [it] not, to him it is sin.

[2Pe 1:4 KJV] 4 Whereby are given unto us exceeding great and precious promises: that by these ye might be partakers of the divine nature, having escaped the corruption that is in the world through lust.

[1Jo 3:4-15 KJV] 4 Whosoever committeth sin transgresseth also the law: for sin is the transgression of the law. 5 And ye know that he was manifested to take away our sins; and in him is no sin. 6 Whosoever abideth in him sinneth not: whosoever sinneth hath not seen him, neither known him. 7 Little children, let no man deceive you: he that doeth righteousness is righteous, even as he is righteous. 8 He that committeth sin is of the devil; for the devil sinneth from the beginning. For this purpose the Son of God was manifested, that he might destroy the works of the devil. 9 Whosoever is born of God doth not commit sin; for his seed remaineth in him: and he cannot sin, because he is born of God. 10 In this the children of God are manifest, and the children of the devil: whosoever doeth not righteousness is not of God, neither he that loveth not his brother. 11 For this is the message that ye heard from the beginning, that we should love one another. 12 Not as Cain, [who] was of that wicked one, and slew his brother. And wherefore slew he him? Because his own works were evil, and his brother's righteous. 13 Marvel not, my brethren, if the world hate you. 14 We know that we have passed from death unto life, because we love the brethren. He that loveth not [his] brother abideth in death. 15 Whosoever hateth his brother is a murderer: and ye know that no murderer hath eternal life abiding in him.

[1Jo 5:17 KJV] 17 All unrighteousness is sin: and there is a sin not unto death.