His argument was simple, he didn’t see anywhere that he has been taught or seen in the bible that says anyone besides God, Christ, and Angels were in heaven.
Well, as The_Scott has pointed out; you have been given plenty. Take for instance the good thief and some passages in Revelations. Now, this is starting to appear to me or rather I am beginning to recognize how this point can actually become troublesome for some people. When I first read your question I thought you needed a simple answer that is available and people posted them for you. However, I can see how this question can become an obstacle for people to move forward in the faith. It did not seem to me to be the case with your question at first, but people have a way of rationalizing Sacred Scripture that let this very act and ability serve to confirm to us all that the Catholic Church is the Church Our Lord Jesus Christ established : "And I tell you that you are Peter, and on this rock I will build my church, and the gates of Hades will not overcome it. (Mat. 16:18).
I think we need to ask ourselves, in the light of the reality that people can turn the teaching of Sacred Scripture upside down and that millions of churches can be founded with that many different interpretations; how can we think that God did not leave behind a Church to guide us? How can some claim that; well, He did but then it became bad and so others needed to be established? Our Lord Jesus Christ established one Church and it will remain until the end of time, rather people like her teachings or not and rather Catholics sin or not. The Church He established is guided by the Holy Spirit and it is this Spirit and that Church that illumines Sacred Scripture for us and guides us.
I am ignorant and my admission of this fact is not pretentious humility. I am being totally honest and sincere when I write that I am ignorant. I am. In my ignorance and as I learn; I consider how just from reading the Bible it is not obvious nor is it necessarily intellectually deductible that God is a triune God and that it is good to baptize our infants. These things are there, but, purely by the use of my intellect I can not say that I would have been able to deduce such truths. This and many other teachings of the Church, e.g. original sin, Mary, etc… are not obvious but the Catholic Church brings them to light and once you SEE them and recognize that they are all part of a harmonious whole - there can be no question that the Catholic Church is guided by the Holy Spirit. At least for me, it has worked this way.
There are two famous old time professor of Yale University who have dedicated their life to the study of the Bible and Christianity. I have been astonished by their ‘intellectual’ conclusions. They claim that homosexuality is fine according to scripture and they twist and turn certain verses to this end and finally and get ready for this one; they claim that the reason Paul wrote in the manner that he did at the beginning of the letter to the Romans was because he was ignorant, backwards and a man of his time. They go on about how we are more civilized, advanced and educated now. How that for turning the teachings of Sacred Scripture upside down? And, these are the suppose great intellectuals from the creme de la creme educational institutions.
Here a Bishop from The Church of England rebuttals the teachings of the Catholic Church regarding this matter these are his rationalizations:
Wright: There is Luke 23, where Jesus says to the good thief on the cross, “Today you will be with me in Paradise.” But in Luke, we know first of all that Christ himself will not be resurrected for three days, so “paradise” cannot be a resurrection. It has to be an intermediate state. And chapters 4 and 5 of Revelation, where there is a vision of worship in heaven that people imagine describes our worship at the end of time. In fact it’s describing the worship that’s going on right now. If you read the book through, you see that at the end we don’t have a description of heaven, but, as I said, of the new heavens and the new earth joined together.
time.com/time/world/article/0,8599,1710844,00.html#ixzz22nksUw00
I think you want to establish the value of the Church that teaches these truths. Also, there is that old question; where in the Bible does it say scripture only? In the light of how people could completely misinterpret the teachings of Sacred Scripture; how can God leave it on its own? It would really be as if to leave nothing, because anything could go really without guidance.
He agrees that all must be pure to be in the sight of God, and so everyone is in a ‘purgatory’ like existence. That is why I am looking for passages that mention the saints or just men.
I could tell someone with limited knowledge about mathematics that 3 + 1 = 4 and the person may know and understand the logic of addition and know 4 and I but not 3. And so, this person may say, no this is not true nor can it be. I think this happens to some people when it comes to some teachings of Holy Mother Church but then they learn the value of three find themselves in awe or just thnking ‘spectacular’.
Well, I hope this helps. Sorry for rambling on…