I know that the Bible assures us that, in Heaven, there will be a vast crowd of people from every nation, tribe, people and language, standing before the throne of God in Heaven, who attribute their salvation to God and the Lamb at the centre of the throne. Read that in Revelation 7:9-17 and note how the multitude is too vast for humans to number. But God knows their number and their names.
I believe the promises in the Bible, especially the assurance that Christians can be "confident of this, that he who began a good work in you will carry it on to completion until the day of Christ Jesus." Philippians 1:5-6. I also believe what Jesus said, that the work of God is to believe the One He sent (Himself - John 6:29) and that we come to Him to have life eternal (John 5:38-40) and that Jesus never turns away anyone who comes to Him (John 6:37). He also said that His sheep come to Him, He holds them in His hand and "they shall never perish; no-one can snatch them out of my hand" (John 10:25-30). He also said that He returned to Heaven in order to prepare a place for His own, in His Father's realm (John 14:1-4).
I know that I belong to Jesus now. I believe Jesus. Heaven is promised to those who have been given saving faith in Him.
Matthew 5:12 -because great is your reward in heaven
Matthew 7:21 -those doing the will of my Father will enter the kingdom of heaven
Matthew 19:14 -the kingdom of heaven belongs to such ones
Matthew 19:21 -and you will have treasures in heaven
Luke 10:20 -your names are written in heaven
John 14:2-3 “In my Father’s house are many mansions: if it were not so, I would have told you. I go to prepare a place for you. And if I go and prepare a place for you, I will come again and receive you unto myself; that where I am, there ye may be also.”
John 17:24 “Father, I want those you have given me to be with me where I am and to see my glory, the glory you have given me because you loved me before the creation of the world.”
1 Corinthians 15:46-53 -as is the man from heaven [Jesus] so also are those who are of heaven And just as we have borne the likeness of the earthly man, so shall we bear the likeness of the man from heaven... we will all be changed - in a flash, in the twinkling of an eye, at the last trumpet... the dead will be raised imperishable and we will be changed...
2 Corinthians 5:1-2 -an eternal house in heaven, not built by hands... to be clothed with our heavenly dwelling
Romans 8:15-17 -co-heirs with Christ... in order that we may also share in his glory
Philippians 1:20-24 & 27 -I desire to depart [in death] and be with Christ, which is better by far [for He is in heaven, and so will I be once I die!]
Phil. 3:14 -I press on towards the goal to win the prize for which God has called me heavenwards in Christ
Philippians 3:20 -But our citizenship is in heaven
2 Timothy 4:18 -bring me safely to his heavenly kingdom
Hebrews 11:5 – “By faith Enoch was taken up to heaven without dying: he disappeared because God took him’
Verses 10 to 16 – “Abraham was confidently looking forward to a city with eternal foundations, a city designed and built by God… But they were looking for a better place, a heavenly home.”
Hebrews 12:22 – Christians come to Mount Zion, the city of God, heavenly Jerusalem where countless angels are gathered (not earthly Jerusalem).
Verse 23 – “You have come to the assembly of God’s firstborn children whose names are written in heaven. You have come to God himself, who is the judge over all things. You have come to the spirits of the righteous ones in Heaven who have now been made perfect. You have come to Jesus [who is in Heaven]…”
Revelation 3:21 where Jesus says, “To him who overcomes, I will give the right to sit with me on my throne, just as I overcame and sat down with my Father on his throne.” The throne Jesus speaks of is in Heaven – see Rev. chapter 5.
Revelation 7:9-11 where a great multitude of people who have come out of the great tribulation on Earth are standing before God and Christ sitting on the throne of Heaven, worshipping.
Revelation 6:9-11 -under [heaven’s] altar I saw the souls of those who had been slain… for their testimony
Yes, I am assured that I will go to Heaven.