Titus 1:15

To the pure, all things are pure; but to the corrupt and unbelieving, nothing is pure; both their mind and their conscience are corrupted.

Romans 14:20

Do not, for the sake of food, tear down the work of God. All things indeed are [ceremonially] clean, but they are wrong for the person who eats and offends [another’s conscience in the process].

Romans 14:23

But he who is uncertain [about eating a particular thing] is condemned if he eats, because he is not acting from faith. Whatever is not from faith is sin [whatever is done with doubt is sinful].

Romans 14:14

I know and am convinced [as one] in the Lord Jesus that nothing is unclean [ritually defiled, and unholy] in itself; but [nonetheless] it is unclean to anyone who thinks it is unclean.

Matthew 15:18

But whatever [word] comes out of the mouth comes from the heart, and this is what defiles and dishonors the man.

Acts 10:15

And the voice came to him a second time, “What God has cleansed and pronounced clean, no longer consider common (unholy).”

Proverbs 21:4


Haughty and arrogant eyes and a proud heart,
The lamp of the wicked [their self-centered pride], is sin [in the eyes of God].

Haggai 2:13

Then Haggai said, “If one who is [ceremonially] unclean because of [contact with] a corpse touches any of these [articles of food], will it be unclean?” And the priests answered, “It will be unclean.” [Ceremonial uncleanness, like sin, is infectious.]

Zechariah 7:5-6

“Speak to all the people of the land and to the priests, saying, ‘When you fasted and mourned in the fifth and seventh months these seventy years [that you were in exile], was it actually for Me that you fasted?

Luke 11:39-41

But the Lord said to him, “Now you Pharisees clean the outside of the cup and plate [as required by tradition]; but inside you are full of greed and wickedness.

1 Corinthians 6:12-13

Everything is permissible for me, but not all things are beneficial. Everything is permissible for me, but I will not be enslaved by anything [and brought under its power, allowing it to control me].

1 Corinthians 8:7

However, not all [believers] have this knowledge. But some, being accustomed [throughout their lives] to [thinking of] the idol until now [as real and living], still eat food as if it were sacrificed to an idol; and because their conscience is weak, it is defiled (guilty, ashamed).

1 Corinthians 10:23

All things are lawful [that is, morally legitimate, permissible], but not all things are beneficial or advantageous. All things are lawful, but not all things are constructive [to character] and edifying [to spiritual life].

1 Corinthians 10:25

[Regarding meat offered to idols:] Eat anything that is sold in the meat market without asking any questions for the sake of your conscience,

1 Corinthians 10:31

So then, whether you eat or drink or whatever you do, do all to the glory of [our great] God.

1 Corinthians 11:27-29

So then whoever eats the bread or drinks the cup of the Lord in a way that is unworthy [of Him] will be guilty of [profaning and sinning against] the body and blood of the Lord.

1 Timothy 4:3-4

who forbid marriage and advocate abstaining from [certain kinds of] foods which God has created to be gratefully shared by those who believe and have [a clear] knowledge of the truth.

1 Timothy 6:5

and perpetual friction between men who are corrupted in mind and deprived of the truth, who think that godliness is a source of profit [a lucrative, money-making business—withdraw from them].

Hebrews 9:14

how much more will the blood of Christ, who through the eternal [Holy] Spirit willingly offered Himself unblemished [that is, without moral or spiritual imperfection as a sacrifice] to God, cleanse your conscience from dead works and lifeless observances to serve the ever living God?

Hebrews 10:22

let us approach [God] with a true and sincere heart in unqualified assurance of faith, having had our hearts sprinkled clean from an evil conscience and our bodies washed with pure water.

Treasury of Scripture Knowledge

Summary

Unto the pure all things are pure: but unto them that are defiled and unbelieving is nothing pure; but even their mind and conscience is defiled.

Bible References

The pure

Luke 11:39
But the Lord said to him, “Now you Pharisees clean the outside of the cup and plate [as required by tradition]; but inside you are full of greed and wickedness.
Acts 10:15
And the voice came to him a second time, “What God has cleansed and pronounced clean, no longer consider common (unholy).”
Romans 14:14
I know and am convinced [as one] in the Lord Jesus that nothing is unclean [ritually defiled, and unholy] in itself; but [nonetheless] it is unclean to anyone who thinks it is unclean.
1 Corinthians 6:12
Everything is permissible for me, but not all things are beneficial. Everything is permissible for me, but I will not be enslaved by anything [and brought under its power, allowing it to control me].
1 Corinthians 10:23
All things are lawful [that is, morally legitimate, permissible], but not all things are beneficial or advantageous. All things are lawful, but not all things are constructive [to character] and edifying [to spiritual life].
1 Timothy 4:3
who forbid marriage and advocate abstaining from [certain kinds of] foods which God has created to be gratefully shared by those who believe and have [a clear] knowledge of the truth.

Their

1 Corinthians 8:7
However, not all [believers] have this knowledge. But some, being accustomed [throughout their lives] to [thinking of] the idol until now [as real and living], still eat food as if it were sacrificed to an idol; and because their conscience is weak, it is defiled (guilty, ashamed).
Hebrews 9:14
how much more will the blood of Christ, who through the eternal [Holy] Spirit willingly offered Himself unblemished [that is, without moral or spiritual imperfection as a sacrifice] to God, cleanse your conscience from dead works and lifeless observances to serve the ever living God?
Hebrews 10:22
let us approach [God] with a true and sincere heart in unqualified assurance of faith, having had our hearts sprinkled clean from an evil conscience and our bodies washed with pure water.

General references

Leviticus 7:19
‘The meat that comes in contact with anything that is unclean shall not be eaten; it shall be burned in the fire. As for other meat, everyone who is [ceremonially] clean may eat it.
Leviticus 10:10
and to make a distinction and recognize a difference between the holy (sacred) and the common (profane), and between the [ceremonially] unclean and the clean;
Leviticus 11:34
Any of the food which may be eaten, but on which [unclean] water falls, shall become unclean, and any liquid that may be drunk in every container shall become unclean.
Deuteronomy 14:3
“You shall not eat anything that is detestable [to the Lord and forbidden by Him].
Acts 24:16
In view of this, I also do my best and strive always to have a clear conscience before God and before men.