So all people sin constantly and cannot stop?
Below you will find three quotes which are commonly used (out of context) to support the Gnostic idea that we constantly sin in thoughts, words and deeds because of our fallen nature.
1) 1 Kings 8:46 (and the parallel 2 Chr. 6:36)
1 Kings 8:46 If they sin against thee, (for there is no man that sinneth not,) and thou be angry with them, and deliver them to the enemy, so that they carry them away captives unto the land of the enemy, far or near;
+ the parallel:
2 Chr. 6:36 If they sin against thee, (for there is no man which sinneth not,) and thou be angry with them, and deliver them over before their enemies, and they carry them away captives unto a land far off or near;
The above quote is from an earnest prayer by Solomon to God. Solomon was initially a very wise and righteous man, but he later fell away when he married multiple foreign women (700 wives in total, plus 300 concubines) who lured him away from the only true God. In this particular prayer his expressions show that he absolutely believes that people can and should be obedient to God in everything. In this particular prayer he sincerely hopes that God will see the works of repentance from his people Israel, as well as their earnest prayers. We can see that Solomon expects people to repent and be successful in their aim to always be faithful to God’s laws.
Solomon’s expression “there is no man that sinneth not” seems to be a general expression and principle about man on earth, and this is sadly a valid description also today. We know for certain that Solomon did not try to express an inability of man to be faithful to God, because among other things he states “LET YOUR HEART THEREFORE BE PERFECT WITH THE LORD OUR GOD, TO WALK IN HIS STATUTES, AND TO KEEP HIS COMMANDMENTS, as at this day”. He does not propose that such an attempt would always lead to failure. If you repent and “return on to God with all your heart and all with all your soul”, does this not indicate that you also avoid sin?
1 Kings 8:44 If thy people go out to battle against their enemy, whithersoever thou shalt send them, and shall pray unto the Lord toward the city which thou hast chosen, and toward the house that I have built for thy name:45 Then hear thou in heaven their prayer and their supplication, and maintain their cause.46 If they sin against thee, (for there is no man that sinneth not,) and thou be angry with them, and deliver them to the enemy, so that they carry them away captives unto the land of the enemy, far or near;47 Yet if they shall bethink themselves in the land whither they were carried captives, and repent, and make supplication unto thee in the land of them that carried them captives, saying, We have sinned, and have done perversely, we have committed wickedness;48 And so return unto thee with all their heart, and with all their soul, in the land of their enemies, which led them away captive, and pray unto thee toward their land, which thou gavest unto their fathers, the city which thou hast chosen, and the house which I have built for thy name:49 Then hear thou their prayer and their supplication in heaven thy dwelling place, and maintain their cause,50 And forgive thy people that have sinned against thee, and all their transgressions wherein they have transgressed against thee, and give them compassion before them who carried them captive, that they may have compassion on them:—54 And it was so, that when Solomon had made an end of praying all this prayer and supplication unto the Lord, he arose from before the altar of the Lord, from kneeling on his knees with his hands spread up to heaven.—57 The Lord our God be with us, as he was with our fathers: let him not leave us, nor forsake us:58 That he may incline our hearts unto him, to walk in all his ways, and to keep his commandments, and his statutes, and his judgments, which he commanded our fathers.—61 LET YOUR HEART THEREFORE BE PERFECT WITH THE LORD OUR GOD, TO WALK IN HIS STATUTES, AND TO KEEP HIS COMMANDMENTS, as at this day.
In 2 Chr. 6 the wicked are contrasted with the righteous, and Solomon absolutely trusts that people have the capability to “fear thee, to walk in thy ways, so long as they live”:
2 Chr. 6:14 And said, O Lord God of Israel, there is no God like thee in the heaven, nor in the earth; which keepest covenant, and shewest mercy unto thy servants, that walk before thee with all their hearts:—23 Then hear thou from heaven, and do, and judge thy servants, by requiting the wicked, by recompensing his way upon his own head; and by justifying the righteous, by giving him according to his righteousness.—30 Then hear thou from heaven thy dwelling place, and forgive, and render unto every man according unto all his ways, whose heart thou knowest; (for thou only knowest the hearts of the children of men:)31 That they may fear thee, to walk in thy ways, so long as they live in the land which thou gavest unto our fathers.
and we read on:
2 Chr. 6:37 Yet if they bethink themselves in the land whither they are carried captive, and turn and pray unto thee in the land of their captivity, saying, We have sinned, we have done amiss, and have dealt wickedly;38 If they return to thee with all their heart and with all their soul in the land of their captivity, whither they have carried them captives, and pray toward their land, which thou gavest unto their fathers, and toward the city which thou hast chosen, and toward the house which I have built for thy name:39 Then hear thou from the heavens, even from thy dwelling place, their prayer and their supplications, and maintain their cause, and forgive thy people which have sinned against thee.
2) Ecc. 7:20 For there is not a just man upon earth, that doeth good, and sinneth not
The author of Ecclesiastes has also said ”eat, drink and be merry” which must be read in its proper context, and he sometimes sounds a bit pessimistic about man in general. The author has the right to express himself with hyperboles, general principles, analogies and poetic comparisons, depending on what he wants to convey. The author describes righteous and God-fearing people, and he contrasts them with the wicked. This means that also this author is of the opinion that man can be a righteous and godly individual who does what is right.
Ecc. 7:16 Be not righteous over much; neither make thyself over wise: why shouldest thou destroy thyself ?17 Be not over much wicked, neither be thou foolish: why shouldest thou die before thy time?18 It is good that thou shouldest take hold of this; yea, also from this withdraw not thine hand: for he that feareth God shall come forth of them all.19 Wisdom strengtheneth the wise more than ten mighty men which are in the city.20 For there is not a just man upon earth, that doeth good, and sinneth not.21 Also take no heed unto all words that are spoken; lest thou hear thy servant curse thee:22 For oftentimes also thine own heart knoweth that thou thyself likewise hast cursed others.23 All this have I proved by wisdom: I said, I will be wise; but it was far from me.
Ecc. 9:1 For all this I considered in my heart even to declare all this, that the righteous, and the wise, and their works, are in the hand of God: no man knoweth either love or hatred by all that is before them.2 All things come alike to all: there is one event to the righteous, and to the wicked; to the good and to the clean, and to the unclean; to him that sacrificeth, and to him that sacrificeth not: as is the good, so is the sinner; and he that sweareth, as he that feareth an oath.
3) Prov. 20:9 Who can say, I have made my heart clean, I am pure from my sin?
We have no authority to cleanse ourselves from sin, but we can be cleansed when we confess our sins and repent. The text in Proverbs often mirrors the reality through poetry, analogies and general principles, which means that the text does not necessarily convey the truth in a literal sense. Proverbs 20:9 poses an important question to think about, because who can really say that he/she has never sinned? The case is usually the opposite – that people are unclean due to ongoing sins. Not because they have to commit sins but because of their own choices. The point in likely to express the fact that sinning is (sadly) common among people. Babies have never sinned and cannot even do so because they are not aware of the law, but they can on the other hand not read any advice in Proverbs so the text is not written for their sake. If Proverbs 20:9 should be read in a literal sense as though there is absolutely no one under the sun who has a pure heart because of constant sins, the chapter and the book of Proverbs contain multiple contradictions. We can even read in the verses prior to Prov. 20:9 and right after it, that man can indeed cease from strife, can be just, pure, etc.
Prov. 20:3 It is an honour for a man to cease from strife: but every fool will be meddling.—7 The just man walketh in his integrity: his children are blessed after him.8 A king that sitteth in the throne of judgment scattereth away all evil with his eyes.—11 Even a child is known by his doings, whether his work be pure, and whether it be right.—15 There is gold, and a multitude of rubies: but the lips of knowledge are a precious jewel.—19 He that goeth about as a talebearer revealeth secrets: therefore meddle not with him that flattereth with his lips.20 Whoso curseth his father or his mother, his lamp shall be put out in obscure darkness.—22 Say not thou, I will recompense evil; but wait on the Lord, and he shall save thee.23 Divers weights are an abomination unto the Lord; and a false balance is not good.—30 The blueness of a wound cleanseth away evil: so do stripes the inward parts of the belly.
You can also read about other common verses that are used to promote a sinful life – Rom. 3:10 here and 1 John 1:8 here.