I will quote you scriptures first on vanity and then iniquity and then what will happen to you if you do not change your ways, then what you can do to help mend your ways.
Iniquity and vanity are very similar, which is wickedness.
All text taken from the King James Bible
Ecclesiastes was written by the Preacher (see chapter 1:1) so when it says "I" in the Eccl. scriptures, it is referring to "the preacher".
Eccl.1:2 - Vanity of vanities, saith the Preacher, vanity of vanities; all is vanity.
Eccl.1:14 - I have seen all the works that are done under the sun; behold, all is vanity and vexation of spirit.
Eccl.1:15 - All things have I seen in the days of my vanity: there is a just man that perisheth in his righteousness, and there is a wicked man that prolongeth his life in his wickedness.
Most of Ecclesiastes talks about vanity.
Job 15:31 - Let not him that is deceived trust in vanity: for vanity shall be his recompence.
Ps.10:7 - His mouth is full of cursing and deceit and fraud: under his tongue is mischief and vanity ( or, iniquity)
James 3:5 - Even so the tongue is a little member, and boasteth great things. Behold, how great a matter a little fire kindleth!
James 3:6 - And the tongue is a fire, a world of iniquity: so is the tongue among our members, that it defileth the whole body, and setteth on fire the course of nature; and it is set on fire of hell.
James 3:7 - For every kind of beast, and of birds and of serpents, and things in the sea, is tamed, and hath been tamed of mankind:
James 3:8 -But the tongue can no man tame; it is an unruly evil full of deadly poison.
You can read all of James chapter 3 for yourself if you like.
Job 4:8 - Even as I (Job) have seen, they that plow iniquity, and sow wickness, reap the same.
Job 4:9 - By the blast of God they perish, and by the breath of his nostrils are they consumed.
Prov. 22:8 - He that soweth iniquity shall reap vanity: and the rod of his anger shall fail. (or, and with the rod of his anger he shall be consumed.)
Ps. 94:3 - LORD, how long shall the wicked, how long shall the wicked triumph?
Ps. 94:4 - How long shall they utter and speak hard things? and all the workers of iniquity boast themselves?
Ps.92:2 - Lift up thyself, thou judge of the earth: render a reward to the proud.
Prov. 16:6 - By mercy, and truth iniquity is purged: and by fear of the LORD men depart from evil.
Is.53:6 - All we like sheep have gone astray; we have turned everyone to his own ways; and the LORD hath laid on him the iniquity of us all. See - Fountain of Living Waters vs. Cisterns
Ezek.18:30 - 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.
Matt.7:21 - Not every one that saith unto me Lord, Lord, shall enter into the kingdom of heaven; but he that doeth the will of my Father which is in heaven. See - Not Every Body Shall Enter the Kingdom of Heaven
Matt.7:22 - Many will say to me in that day Lord, Lord, have we not prophesied in thy name? and in thy name have cast out devils? and in thy name done many wonderful works?
Matt.7:23 - And then will I (Jesus) profess unto them, I never knew you: depart from me, ye that work iniquity
I Cor.13:6 - Rejoiceth not in iniquity, but rejoiceth in the truth;
Matt.24:12 - And because iniquity shall abound, the love of many shall wax cold. (the love of God shall fade away or drop off)
II Tim.2:19 - Nevertheless the foundation of God standeth sure, having the seal, The Lord knoweth them that are his. And, Let every one that nameth the name of Christ depart from iniquity See Sign, Mark and Seal of God
Heb.1:9 - Thou hast loved righteousness, and hated iniquity; therefore God even thy God, hath annointed thee with oil of gladness avove thy fellows.
Titus 2:14 - (Jesus) Who gave himself for us, that he might redeem us from iniquity, and purify unto himself a peculiar people, zealous of good works.
Matt.13:41 - The Son of man shall send forth his angels, and they shall gather out of his kingdom all things that offend, and them which do iniquity;
Matt.13:42 - And shall cast them into a furnace of fire: there shall be wailing and gnashing of teeth. See - Furnace of Fire/Lake of Fire
Eccl.8:5 - Whoso keepth the commandment shall feel (or, know) no evil thing: and a wise man's heart discerneth both time and judgment.
The only way that you are going to make it into God's kingdom is to depart from iniquity and follow the commandments of God. See -Fountain of Living Waters vs. Cisterns