"...let us draw near with a true heart in full assurance of faith, having our hearts sprinkled from an evil conscience and our bodies washed with pure water. Let us hold fast the confession of our hope without wavering, for He who promised is faithful. And let us consider one another in order to stir up love and good works, not forsaking the assembling of ourselves together, as is the manner of some, but exhorting one another, and so much the more as you see he Day approaching." Hebrews 10:22-25

Conscience
Witnesses in man.
Prov 20:27 The spirit of a man is the lamp of the Lord, Searching all the inner depths of his heart.

Rom 2:15 who show the work of the law written in their hearts, their conscience also bearing witness, and between themselves their thoughts accusing or else excusing them)
Accuses of sin.

Gen 42:21 Then they said to one another, “We are truly guilty concerning our brother, for we saw the anguish of his soul when he pleaded with us, and we would not hear; therefore this distress has come upon us.”

2 Sam 24:10 And David’s heart condemned him after he had numbered the people. So David said to the Lord, “I have sinned greatly in what I have done; but now, I pray, O Lord, take away the iniquity of Your servant, for I have done very foolishly.”
Matt 27:3 Then Judas, His betrayer, seeing that He had been condemned, was remorseful and brought back the thirty pieces of silver to the chief priests and elders,

Acts 2:37 Now when they heard this, they were cut to the heart, and said to Peter and the rest of the apostles, “Men and brethren, what shall we do?”
Should affirm believers.

Job 27:6 My righteousness I hold fast, and will not let it go; My heart shall not reproach me as long as I live.
Acts 23:1 Then Paul, looking earnestly at the council, said, “Men and brethren, I have lived in all good conscience before God until this day.”

Acts 24:16 This being so, I myself always strive to have a conscience without offense toward God and men.
Acts 26:9 “Indeed, I myself thought I must do many things contrary to the name of Jesus of Nazareth.
Rom 9:1 I tell the truth in Christ, I am not lying, my conscience also bearing me witness in the Holy Spirit,
Rom 14:22 Do you have faith? Have it to yourself before God. Happy is he who does not condemn himself in what he approves.
Heb 13:18 Pray for us; for we are confident that we have a good conscience, in all things desiring to live honorably.
1 Pet 3:16 having a good conscience, that when they defame you as evildoers, those who revile your good conduct in Christ may be ashamed.

1 Pet 3:21 There is also an antitype which now saves us-baptism (not the removal of the filth of the flesh, but the answer of a good conscience toward God), through the resurrection of Jesus Christ,

Only Christ’s blood can purify.
Heb 9:14 how much more shall the blood of Christ, who through the eternal Spirit offered Himself without spot to God, cleanse your conscience from dead works to serve the living God?
Heb 10:2–10 For then would they not have ceased to be offered? For the worshipers, once purified, would have had no more consciousness of sins. 3 But in those sacrifices there is a reminder of sins every year. 4 For it is not possible that the blood of bulls and goats could take away sins. 5 Therefore, when He came into the world, He said: “Sacrifice and offering You did not desire, But a body You have prepared for Me. 6 In burnt offerings and sacrifices for sin You had no pleasure. 7 Then I said, ‘Behold, I have come- In the volume of the book it is written of Me- To do Your will, O God.’ ” 8 Previously saying, “Sacrifice and offering, burnt offerings, and offerings for sin You did not desire, nor had pleasure in them” (which are offered according to the law), 9 then He said, “Behold, I have come to do Your will, O God.” He takes away the first that He may establish the second. 10 By that will we have been sanctified through the offering of the body of Jesus Christ once for all.

Heb 10:22 let us draw near with a true heart in full assurance of faith, having our hearts sprinkled from an evil conscience and our bodies washed with pure water.
Walk obediently for sake of.

Rom 13:5 Therefore you must be subject, not only because of wrath but also for conscience’ sake.

2 Cor 1:12 For our boasting is this: the testimony of our conscience that we conducted ourselves in the world in simplicity and godly sincerity, not with fleshly wisdom but by the grace of God, and more abundantly toward you.
1 Tim 1:19 having faith and a good conscience, which some having rejected, concerning the faith have suffered shipwreck,
1 Tim 3:9 holding the mystery of the faith with a pure conscience.

1 Pet 2:19 For this is commendable, if because of conscience toward God one endures grief, suffering wrongfully.
1 John 3:21 Beloved, if our heart does not condemn us, we have confidence toward God.

Of others, not to be offended.

Rom 14:21 It is good neither to eat meat nor drink wine nor do anything by which your brother stumbles or is offended or is made weak.

1 Cor 10:28–32 But if anyone says to you, “This was offered to idols,” do not eat it for the sake of the one who told you, and for conscience’ sake; for “the earth is the Lord’s, and all its fullness.” 29 “Conscience,” I say, not your own, but that of the other. For why is my liberty judged by another man’s conscience? 30 But if I partake with thanks, why am I evil spoken of for the food over which I give thanks? 31 Therefore, whether you eat or drink, or whatever you do, do all to the glory of God. 32 Give no offense, either to the Jews or to the Greeks or to the church of God,

Ministers should commend themselves to that of their people.
2 Cor 4:2 But we have renounced the hidden things of shame, not walking in craftiness nor handling the word of God deceitfully, but by manifestation of the truth commending ourselves to every man’s conscience in the sight of God.
2 Cor 5:11 Knowing, therefore, the terror of the Lord, we persuade men; but we are well known to God, and I also trust are well known in your consciences.
Of wicked unbelievers.

1 Tim 4:2 speaking lies in hypocrisy, having their own conscience seared with a hot iron,
Titus 1:15 To the pure all things are pure, but to those who are defiled and unbelieving nothing is pure; but even their mind and conscience are defiled.
Contemp

MacArthur, J. (1999). The MacArthur topical Bible : New King James Version (256). Nashville, Tenn.: Word Pub.