Contrary to what kcwildman has posted, there are very early references to Hell in the Scriptures, beginning in the Old Testament. Hell is also referred to in other passages using different terms, such as Hades, the bottomless pit, the Lake of Fire, etc. There are many more references than I am listing here.
Numbers 26:10: “And the earth opened her mouth, and swallowed them up together with Korah, when that company died, what time the fire devoured two hundred and fifty men: and they became a sign.”
Psalm 9:17: “The wicked shall be turned into hell, and all the nations that forget God.”
Psalm 139:8: “If I ascend up into heaven, thou art there: if I make my bed in hell, behold, thou art there."
Isaiah 5:14: “Therefore hell hath enlarged herself, and opened her mouth without measure: and their glory, and their multitude, and their pomp, and he that rejoiceth, shall descend into it.”
Ezekiel 31:16: “I made the nations to shake at the sound of his fall, when I cast him down to hell with them that descend into the pit…”
Matthew 5:28,29: “But I say unto you, That whosoever looketh on a woman to lust after her hath committed adultery with her already in his heart. And if thy right eye offend thee, pluck it out, and cast it from thee: for it is profitable for thee that one of thy members should perish, and not that thy whole body should be cast into hell.”
Matthew 16:18: “And I say also unto thee, That thou art Peter, and upon this rock I will build my church; and the gates of hell shall not prevail against it.”
Matthew 23:15: “Woe unto you, scribes and Pharisees, hypocrites! for ye compass sea and land to make one proselyte, and when he is made, ye make him twofold more the child of hell than yourselves.”
Matthew 23:33,34: “Ye serpents, ye generation of vipers, how can ye escape the damnation of hell? Wherefore, behold, I send unto you prophets, and wise men, and scribes: and some of them ye shall kill and crucify; and some of them shall ye scourge in your synagogues, and persecute them from city to city."
Mark 9:45,46: “And if thy foot offend thee, cut it off: it is better for thee to enter halt into life, than having two feet to be cast into hell, into the fire that never shall be quenched: Where their worm dieth not, and the fire is not quenched.”
Luke 10:15: “And thou, Capernaum, which art exalted to heaven, shalt be thrust down to hell.”
Luke 12:5: “But I will forewarn you whom ye shall fear: Fear him, which after he hath killed hath power to cast into hell; yea, I say unto you, Fear him.”
Luke 16:23: “And in hell he lift up his eyes, being in torments…”
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.”
2 Peter 2:4: “For if God spared not the angels that sinned, but cast them down to hell, and delivered them into chains of darkness, to be reserved unto judgment…”
Revelation 1:18: “I am he that liveth, and was dead; and, behold, I am alive for evermore, Amen; and have the keys of hell and of death.”
Satan is called "the angel of the bottomless pit" (Revelation 9:11).
Revelation 20:13-15: “And the sea gave up the dead which were in it; and death and hell delivered up the dead which were in them: and they were judged every man according to their works. And death and hell were cast into the lake of fire. This is the second death. And whosoever was not found written in the book of life was cast into the lake of fire.”
Jude 1:17-19: But, dear friends, remember what the apostles of our Lord Jesus Christ foretold. They said to you, “In the last times [last days] there will be scoffers who will follow their own ungodly desires.” These are the people who divide you, who follow mere natural instincts and do not have the Spirit.