Here is some of what the Lord said about the church in Thyatira, "'I know your deeds, and your love and faith and service and perseverance, and that your deeds of late are greater than at first. 'But I have this against you, that you tolerate the woman Jezebel, who calls herself a prophetess, and she teaches and leads My bond-servants astray, so that they commit acts of immorality and eat things sacrificed to idols. 'And I gave her time to repent; and she does not want to repent of her immorality. 'Behold, I will cast her upon a bed of sickness, and those who commit adultery with her into great tribulation, unless they repent of her deeds. 'And I will kill her children with pestilence; and all the churches will know that I am He who searches the minds and hearts; and I will give to each one of you according to your deeds.'" (Rev. 2:19-23 NASB, bolding mine ACW)

Corruption in the church without correction or rebuke is like a pestilence with consequences far greater than any physical disease or plague. A word in the bible used to refer to this kind of power or influence is "leaven."

Leaven, literally in the bible, is a fermenting substance. When mixed into dough, it causes it to rise. Leaven does not affect only a portion of the dough but the whole mass. (1 Cor. 5:6).

In the Bible, the word leaven is used with a good and bad connotation. Many times, it is used figuratively to refer to corruption of teachings or practices and its pervasive influence. Leaven was referred to the teaching of the Pharisees in Matthew 16:6-12. Their teaching was false, hypocritical, and corrupted. This leaven becomes more dangerous to a local church when mixed into the hearts of brethren with no rebuke or correction. The danger increases because if the element is blended so thoroughly, it can become very difficult to spot; even by the most informed and observing persons who are part of the whole; they themselves having become contaminated.

An illustration of this can be seen in Galatians 2:11-21, where Paul speaks of Cephas (Peter), brethren who came from James (Jewish Christians), and Barnabas. These members of the church were corrupted by the sinful practice of religio-national prejudice. Past teachings and practices regarding the Gentiles were continued. These misguided Jewish Christians treated the Gentile Christians as a lower class of Christians. This was evident when the Jewish Christians would withdraw and hold themselves aloof in their association with the Gentile Christians. Paul recognized their error and made rebuke and correction.

Remember it was Peter that spoke to the Gentiles, "And he said to them, "You yourselves know how unlawful it is for a man who is a Jew to associate with a foreigner or to visit him; and yet God has shown me that I should not call any man unholy or unclean." (Acts 10:28 NASB).

Barnabas had worked with Paul in debating the Judaizing Christians who had made circumcision a condition of salvation for the Gentiles. Acts 15:2

If Peter (one of the twelve apostles) and Barnabas can be drawn away from the truth by some misguided individuals, even if by the fear of them, as is evident in Galatians 2, what about you and I? It becomes very important that we diligently guard continuously against corruption.

The solution for each member of the church in guarding against corruption is found in the N.T. statement, "But like the Holy One who called you, be holy yourselves also in all your behavior;" (1 Peter 1:15 NAS). Holy, in this passage means pure, clean, and undefiled.

Our conduct or behavior begins with our minds or hearts. Jesus said, "But the things that proceed out of the mouth come from the heart, and those defile the man. "For out of the heart come evil thoughts, murders, adulteries, fornications, thefts, false witness, slanders. "These are the things which defile the man; but to eat with unwashed hands does not defile the man." (Matt. 15:18-20 NASB).

Our minds can be filled with things that do not belong and things that do belong. Those things that do not belong must be removed. Those things that do belong must remain. However, without your work, impure thoughts do not run away and pure thoughts do not make a home in your mind. Thus is born personal responsibility.

When Saul, the first human king of Israel, rejected God, the Lord sent Samuel to the house of Jesse to show Samuel whom He had chosen to take Saul's place as king. When Samuel came to Jesse of Bethlehem, Samuel began to look over the sons of Jesse and thought that surely the Lord was going to pick Eliab the eldest son to be anointed. "But the LORD said to Samuel, "Do not look at his appearance or at the height of his stature, because I have rejected him; for God sees not as man sees, for man looks at the outward appearance, but the LORD looks at the heart."" (1 Sam. 16:7 NASB). The Lord is concerned about the state and activity of a person's mind or heart, knowing that the outside will follow that which is from within. If the Lord is concerned and looking at our hearts, should we not look at our own hearts?

When Solomon, the son of David was about to become king, the Lord said to Solomon, "As for you, my son Solomon, know the God of your father, and serve Him with a whole heart and a willing mind; for the LORD searches all hearts, and understands every intent of the thoughts. If you seek Him, He will let you find Him; but if you forsake Him, He will reject you forever." (1 Chron. 28:9 NASB, bolding mine ACW). A willing mind implies a mind that intends. A mind that intends implies a mind that purposes. A mind that purposes implies a mind that chooses. A mind that chooses implies free moral agency. Solomon had to make a choice, either: (1) with his whole heart and willing mind serve and seek the Lord and be blessed or (2) forsake the Lord and be rejected by God.

The things above regarding the heart, mind, and behavior were mentioned to give a useful basis in which to build a holy and pure heart, and as a result, the ability to combat leaven. God does not want a fair-weather member of the church. We are to give our all to Him and at all times be loyal. Serving God with a whole heart and willing mind will accomplish just that.

Reject and put away impure thoughts. Practice acquiring and maintaining pure thoughts. Getting and maintaining pure thoughts is accomplished by doing something.

Paul said, "Finally, brethren, whatever is true, whatever is honorable, whatever is right, whatever is pure, whatever is lovely, whatever is of good repute, if there is any excellence and if anything worthy of praise, let your mind dwell on these things." (Philip. 4:8 NASB). We do not have a lack of information concerning the heart and mind, and what our behavior ought to be. The New Testament is full of God's instructions and teachings in this area. Read, study, and meditate on what God has given you in His word. By dwelling, thinking, or meditating on God's word, will at those moments help keep you in tune with what Paul mentioned in Philippians 4:8. Other helps such as prayer, worship, and engaging in good deeds are not to be neglected.

Paul also said, "But now you also, put them all aside: anger, wrath, malice, slander, and abusive speech from your mouth. "Do not lie to one another, since you laid aside the old self with its evil practices, and have put on the new self who is being renewed to a true knowledge according to the image of the One who created him — a renewal in which there is no distinction between Greek and Jew, circumcised and uncircumcised, barbarian, Scythian, slave and freeman, but Christ is all, and in all. "And so, as those who have been chosen of God, holy and beloved, put on a heart of compassion, kindness, humility, gentleness and patience; bearing with one another, and forgiving each other, whoever has a complaint against anyone; just as the Lord forgave you, so also should you. "And beyond all these things put on love, which is the perfect bond of unity. "And let the peace of Christ rule in your hearts, to which indeed you were called in one body; and be thankful. "Let the word of Christ richly dwell within you, . . ." (Col. 3:8-16 NASB). It could not have been said any better, nor will I try.

First Corinthians the fifth chapter gives an illustration of a legitimate disassociation from an erring soul. It was not only the brother's soul who had his father's wife that was at stake, but also the church was at stake. The teaching here shows two possible destructions; (1) he who had his father's wife and (2) the Corinthian church by reason of their arrogance regarding the undisciplined sinner among them and the inevitable contamination of their minds. Action had to be taken to save both the brother who sinned and the church that sinned and was in grave danger of further corruption.

Paul said to the Corinthian church, "Your boasting is not good. "Do you not know that a little leaven leavens the whole lump of dough? "Clean out the old leaven, that you may be a new lump, just as you are in fact unleavened. "For Christ our Passover also has been sacrificed. "Let us therefore celebrate the feast, not with old leaven, nor with the leaven of malice and wickedness, but with the unleavened bread of sincerity and truth." (1 Cor. 5:6-8 NASB).

The leaven that had to be cleaned out was not the sinner, but the wickedness that was in him and the wicked influence that began contaminating the souls of the Corinthian church. Thus, Paul gave the command, "But those who are outside, God judges. "Remove the wicked man from among yourselves." (1 Cor. 5:13 NASB). Disassociating themselves from the unrepentant sinner among them was an effort to save his soul and theirs. When the unfeigned members disassociated themselves from the unrepentant sinner among them, in effect they disassociated themselves from the leaven of corruption.

If the sinner wished to come back into the love and care of the church, he too would have to disassociate himself from the same corruption of sin. This he did. No other specific person in the first Corinthian letter was told to be punished as the one who had his father's wife. Here is what Paul said in his second letter to this church, "Sufficient for such a one is this punishment which was inflicted by the majority, so that on the contrary you should rather forgive and comfort him, lest somehow such a one be overwhelmed by excessive sorrow. "Wherefore I urge you to reaffirm your love for him." (2 Cor. 2:6-8 NASB).