How serious is God about sin?

ANY sin could keep us from God- in thought or deed
1Jn 1:8 If we say that we have no sin, we deceive ourselves, and the truth is not in us.
1Jn 1:9 If we confess our sins, he is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness.
1Jn 1:10 If we say that we have not sinned, we make him a liar, and his word is not in us.
1Jn 2:1 My little children, these things write I unto you, that ye sin not. And if any man sin, we have an advocate with the Father, Jesus Christ the righteous: 1Jn 2:2 And he is the propitiation for our sins: and not for ours only, but also for the sins of the whole world.

Thanks be to God thru Jesus Christ our Lord that He paid a price we could not- we couldn't keep all the rules- we couldn't ever loose the filthy rags of our own righteousness but IN CHRIST we have become the very righteousness of God- thank God for His love and mercy!
(Exodus 34:7) keeping steadfast love for thousands, forgiving iniquity and transgression and sin, but who will by no means clear the guilty, visiting the iniquity of the fathers on the children and the children's children, to the third and the fourth generation."

(Nahum 1:3) The Lord is slow to anger and great in power, and the Lord will by no means clear the guilty. His way is in whirlwind and storm, and the clouds are the dust of his feet.

(Habakkuk 1:13) You who are of purer eyes than to see evil and cannot look at wrong, why do you idly look at traitors and are silent when the wicked swallows up the man more righteous than he?

(Romans 6:23) For the wages of sin is death....

thats the bad news..... thats how serious God is about sin.....

the good news is, of course, Jesus Christ and that He bore the sins of His people, but the picture of Christ Jesus upon the Cross should still serve as reminder to all of us as to how serious God takes sin.... Jesus' agonizing bearing of that sin, the fact that Jesus, in His sinless perfection, had to endure for the first time, separation from God as He cried "my God, my God, why hast thou forsaken me?" the enormity of this event should never be taken lightly or glibly by anyone (not that I am saying that anyone is btw)...

its that the good news can never be properly understood or appreciated without understanding, as much as we possibly can, the incredibly serious nature of the bad news..... that God's holiness is so awesome, so incredible, that as we see Isiah's vision in chapter 6...

(Isaiah 6:1-3) In the year that King Uzziah died I saw the Lord sitting upon a throne, high and lifted up; and the train of his robe filled the temple. Above him stood the seraphim. Each had six wings: with two he covered his face, and with two he covered his feet, and with two he flew. And one called to another and said: "Holy, holy, holy is the Lord of hosts; the whole earth is full of his glory!"

here we see angels.... sinless angels.... who cannot bear to look upon the holy One of Israel (interestingly the NT says that the one Isaiah looked upon in the temple was none other than Jesus Christ, a very important proof for His divinity btw John 12:40-41 ) ... that these angels that are ever before the throne and yet have to, with one set of wings, cover their face and eyes, and with another set cover their feet.... this ought to bring to our remembrance Mt Sinai where the mountain where Moses received the 10 commandments was considered holy ground, the idea of feet declaring the "creaturliness" of all created beings versus the awesome holiness of the Creator.... where the idea of sinful unauthorized treading on holy ground was punishable by death.... this is a bit of a picture at how holy God is, and if the sinless angels have to cover themselves in front of this awesome holiness, how much more ought this holiness affect us (for us to see it now unveiled means certain death) and ought to make us tremble such that we say with Isaiah "Woe is me! For I am lost; for I am a man of unclean lips, and I dwell in the midst of a people of unclean lips; for my eyes have seen the King, the Lord of hosts!" (Isaiah 6:5)

and the angels cry to one another "Holy, Holy Holy..."... Hebrew did not have exclamation marks, underlining, italics, bold, etc.... so the way to emphasis a certain point was to repeat it... you see Jesus often saying "verily verily" or "amen amen" and the like, but in Hebrew the way to maximize the emphasis was to repeat something three times.... so the angels were saying of God, as strongly as possible, the holiness of God..... I just did a quick search on this (the ASV, NASB, NNAS, NLT, NKJV, Holman Christian Standard Bible), so others may want to check it out to see if I am correct on this.... but so far as I can tell, this thrice repetition of "holy, holy, holy" is only found in 2 places in the entire bible, here in Isaiah and again in Revelation 4:8... so this gives us a good picture of the holiness of God and its impact even on the angelic realm, and well as what this vision did to Isaiah himself.....

then, with this view of God in mind, we can start to properly see, as one Puritan writer put it, the awful "sinfulness of sin"... and then, the fact that we are.... mercifully..... graciously.... saved from the just punishment due to that sin.... should rightly cause us to say

Amazing grace! (how sweet the sound)
That sav’d a wretch like me!
I once was lost, but now am found,
Was blind, but now I see.
’Twas grace that taught my heart to fear,
And grace my fears reliev’d;
How precious did that grace appear,
The hour I first believ’d!
Thro’ many dangers, toils and snares,
I have already come;
’Tis grace has brought me safe thus far,
And grace will lead me home.
The Lord has promis’d good to me,
His word my hope secures;
He will my shield and portion be,
As long as life endures.
Yes, when this flesh and heart shall fail,
And mortal life shall cease;
I shall possess, within the veil,
A life of joy and peace.
The earth shall soon dissolve like snow,
The sun forbear to shine;
But God, who call’d me here below,
Will be forever mine.

(Amazing Grace John Newton, Olney Hymns (London: W. Oliver, 1779)