"For I tell you that unless your righteousness surpasses that of the Pharisees and the teachers of the law, you will certainly not enter the kingdom of heaven" ( Matthew 5:20)

"I tell you, on the day of judgment you will have to give an account for every careless word you utter; for by your words you will be justified, and by your words you will be condemned." ( Matthew 12:36-37)

"The Son of Man will send his angels, and they will collect out of his kingdom all causes of sin and all evildoers, and they will throw them into the furnace of fire, where there will be weeping and gnashing of teeth. Then the righteous will shine like the sun in the kingdom of their Father." ( Matthew 13:41-43)

"For this reason the kingdom of heaven may be compared to a king who wished to settle accounts with his slaves ... So my heavenly Father will also do to every one of you, if you do not forgive your brother or sister from your heart." ( Matthew 18:23-35)

"When the Son of Man comes in his glory, and all the angels with him, then he will sit on the throne of his glory. All the nations will be gathered before him, and he will separate people one from another as a shepherd separates the sheep from the goats . . . And these will go away into eternal punishment, but the righteous into eternal life." ( Matthew 25:31-46)

"Not everyone who says to me 'Lord, Lord' will enter the kingdom of heaven, but only the one who does the will of my Father in heaven." ( Matthew 7:21)

"Everyone therefore who acknowledges me before others, I also will acknowledge before my Father in heaven; but whoever denies me before others, I also will deny before my Father in heaven." ( Matthew 10:32-33)

"Truly I tell you, unless you change and become like children, you will never enter the kingdom of heaven. Whoever becomes humble like this child is the greatest in the kingdom of heaven." ( Matthew 18:3-4)

Helpful links to related questions/topics

The Rich Man and Lazarus Woe on Unrepentant Cities The Narrow and Wide Gates The Narrow Door Describe "Heaven" Describe "Hell" How can I avoid going to Hell? Who goes to Hell? Who goes to Heaven? What must I do to go to Heaven?