You have asked some very good questions, and I will try to give you answers from the bible. For every bible verse quoted below there are many others along the same line throughout the bible. I will not attempt to quote more that necessary to answer your questions. If you search the bible you will find the other verses for you will now know what to look for.
You have asked the following questions about sin.
Where in the Holy Scriptures does God's Word best give God's teachings, instructions, and commandments to the following questions?
What is the effects of sin?
Death, Physical and Spiritual
#Ge 2:17 3:19 De 32:51 1Ch 10:13 Pr 11:19 Eze 18:4
#Ro 5:12 6:23
This speaks of Spiritual death
Genesis 2:17 But of the tree of the knowledge of good and evil, thou shalt not eat of it: for in the day that thou eatest thereof thou shalt surely die.
Proverbs 11:19 As righteousness tendeth to life: so he that pursueth evil pursueth it to his own death.
Ezekiel 18:4 Behold, all souls are mine; as the soul of the father, so also the soul of the son is mine: the soul that sinneth, it shall die.
Romans 5:12 Wherefore, as by one man sin entered into the world, and death by sin; and so death passed upon all men, for that all have sinned:
Romans 6:23 For the wages of sin is death; but the gift of God is eternal life through Jesus Christ our Lord.
This speaks of physical death
Genesis 3:19 In the sweat of thy face shalt thou eat bread, till thou return unto the ground; for out of it wast thou taken: for dust thou art, and unto dust shalt thou return.
Deuteronomy 32:50-51 And die in the mount where thou goest up, and be gathered unto thy people, as Aaron, thy brother, died in Mount Hor, and was gathered unto his people. Because ye trespassed against me among the children of Israel at the waters of Meribah-Kadesh, in the wilderness of Zin; because ye sanctified me not in the midst of the children of Israel.
This speaks of both Spiritual and physical death
1 Chronicles 10:13 So Saul died for his transgression which he committed against the LORD, even against the word of the LORD, which he kept not, and also for asking counsel of one that had a familiar spirit, to enquire of it;
THE WICKED SHALL DIE BEFORE THEIR TIME
#Job 22:16 Ps 37:22,38 55:23 Pr 10:27 Ec 7:17 Isa 40:24
Job 22:16 Which were cut down out of time, whose foundation was overflown with a flood:
Psalms 37:22 For such as be blessed of him shall inherit the earth; and they that be cursed of him shall be cut off.
Psalms 37:38 But the transgressors shall be destroyed together: the end of the wicked shall be cut off.
Psalms 55:23 But thou, O God, shalt bring them down into the pit of destruction: bloody and deceitful men shall not live out half their days; but I will trust in thee.
Proverbs 10:27 The fear of the LORD prolongeth days: but the years of the wicked shall be shortened.
Ecclesiastes 7:17 Be not over much wicked, neither be thou foolish: why shouldest thou die before thy time?
Isaiah 40:24 Yea, they shall not be planted; yea, they shall not be sown: yea, their stock shall not take root in the earth: and he shall also blow upon them, and they shall wither, and the whirlwind shall take them away as stubble.
What and how much sin can be present in an ongoing state of repentence?
None! You are either sinless in a state of repentance, or you are a sinner and need to repent. You can not be in a state of repentance and in a state of sin at the same time. See Ezekiel verses below used for another question.
What is unforgiving sin?
Unforgiven sin is spoken of in the bible by Jesus Christ as attributing to Satan the works of God the Holy Spirit . However, there is another class of sin which is spoken of in the bible as being unforgiven, and that is any sin which you have not asked for forgiveness before your death here on Earth. You must have forgiveness before you die, for you will not be forgiven for those sins when you stand before God the judge.
The following verses are on the Sins against the Holy Spirit.
HOLY SPIRIT, The Sin Against
#Isa 63:10 Mt 12:31 Mr 3:29 Ac 5:3 7:51 Eph 4:30
#1Th 5:19 Heb 10:29 1Jo 5:16
Isaiah 63:10 But they rebelled, and vexed his holy Spirit: therefore he was turned to be their enemy, and he fought against them.
Matthew 12:31 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.
Mark 3:29 But he that shall blaspheme against the Holy Ghost hath never forgiveness, but is in danger of eternal damnation:
Acts 5:3 But Peter said, Ananias, why hath Satan filled thine heart to lie to the Holy Ghost, and to keep back part of the price of the land?
Acts 7:51 Ye stiffnecked and uncircumcised in heart and ears, ye do always resist the Holy Ghost: as your fathers did, so do ye.
Ephesians 4:30 And grieve not the holy Spirit of God, whereby ye are sealed unto the day of redemption.
1 Thessalonians 5:19 Quench not the Spirit.
Hebrews 10:29 Of how much sorer punishment, suppose ye, shall he be thought worthy, who hath trodden under foot the Son of God, and hath counted the blood of the covenant, wherewith he was sanctified, an unholy thing, and hath done despite unto the Spirit of grace?
1 John 5:16 If any man see his brother sin a sin which is not unto death, he shall ask, and he shall give him life for them that sin not unto death. There is a sin unto death: I do not say that he shall pray for it.
Can man enter into eternal heaven with any type of sin existing in the past, or present state in ones life?
If sin in your life has never been repented of, then you can not enter heaven, for there is NO sin in heaven, nor will any sin ever be allowed to enter heaven. God has commanded all men to Repent of their sins, and to accept His Son Jesus Christ. There are so many places in the Bible where God commands repentance that I will not attempt to list more that one, below.
Sin that has existed in the past, IF repented of, no longer exists, for God has said that they would no longer be mentioned.
Ezekiel 33:14-16 "Again, when I say unto the wicked, Thou shalt wurely die; if he turn from his sin, and do that which is lawful and right; If the wicked restore the pledge, give again that which he had robbed, walk in the statutes of life, without committing iniquity, he shall surely live; he shall not die. None of his sins that he hath committed shall be mentioned unto him; he hath done that which is lawful and right; he shall surely live."
Ezekiel 18:20-22 "The soul that sinneth, it shall die. The son shall not bear the iniquity of the father, neither shall the father bear the iniquity of the son; the righteousness of the righteous shall be upon him, and the wickedness of the wicked shall be upon him. But if the wicked will turn from all his sins that he hath committed, and keep all my statutes, and do that which is lawful and right, he shall surely live; he shall not die. All his transgressions that he hath committed, they shall not be mentioned unto him; in his righteousness that he hath done he shall live."
Ezekiel 18:30-31 "Therefore, I will judge you, O house of Israel, every one according to his ways, saith the Lord God. Repent, and turn yourselves from all your transgressions; so iniquity shall not be your ruin. Cast away from you all your transgressions, by which ye have transgressed, and make yourself a new heart and a new spirit; for why will ye die, O house of Israel?"
But ---- If there is existing sin in one's present state of life that has not been repented of ---- We assume here that we are speaking of one who has previously repented had received salvation, and was serving the Lord God, and then again commits sins without repenting for them (sin existing in the present state in ones life?).
Ezekiel 18:24, 26 "24 - But when the righteous turneth away from his righteousness, and committeth iniquity, and doeth according to all the abominations that the wicked man doeth, shall he live? All his righteousness that he hath done shall not be mentioned; in his traspass that he hath trespassed, and in his sin that he hath sinned, in them shall he die. " "26 - When a righteous man turneth away from his righteousness, and committeth iniquity, and dieth in them, for his iniquity that he hath done shall he die."
Note here that the man is given until his death to repent. There are two other verses, which speak of God putting a stumbling block before man, (Ezekiel 3:20) and of man trusting in his own righteousness (Ezekiel 33:13) whereby man will loose his salvation and die the second death .
There are many who will, and do, reject the above verses because they do not like the thought that it is possible for them to loose their salvation. They are very happy to accept, and even quote the verses above, and below, these verses, where the verses speak of the sinner repenting, (as above) and thereby not dying, meaning that they gain salvation. They then try to give a different meaning to the word "die" in the above verses. They totally reject all of the other verses, and parables in the Bible that all speak of loss of salvation, putting their trust in a couple of verses that they twist the meaning of.. That, I will not go into here as I have documentation posted on my web site in the files "How to lose your faith" , "Once hired, always hired" , "What is Pharmakeia" , "Religion" , "What is True" , "SALVATION" , and "Denying Jesus".
Be assured that you can not loose your salvation by accident. Once you have salvation, you can only loose it by deliberately turning your back on God and walking away. To turn and to follow the wide path instead of the narrow path. To start disobeying God, which is what sin is, and not repenting.
May God Lead you into All of His Truths
Rev. Jack Barr