I would like to see the Bahai answer to this question.
Mickey,
I will be happy to respond to a pure hearted soul such as your good self.
“could anyone before the advent of Mirza Hussain understand the bible?”
Of course this is true. How could it be otherwise? But please recognize that any response will be attacked and turned upside down by the source of this question, and that is why the questioner is being dealt with in courteous silence. His questions have been answered thoroughly and with concision in the past.
As the Baha’i Faith has no clergy, and I can only give you my best understanding, what I think is being referred to has to do with the following
A The Books of Daniel being “sealed” till the time of the end, meaning that although he himself had the vision, it was not given to him to understand the full meaning.
Daniel 12:9 And he said, “Go thy way, Daniel: for the words [are] closed up and sealed till the time of the end. …”
B It is similarly sealed in Revelation until the time of the end. This is regarding specific visions only, not “understand the Bible”, which is absolutely without foundation to say, as the questioner himself is fully aware.
Revelation Chapter 5
1 And I saw in the right hand of him that sat on the throne a book written within and on the backside, sealed with seven seals.
2 And I saw a strong angel proclaiming with a loud voice, Who is worthy to open the book, and to loose the seals thereof?
3 And no man in heaven, nor in earth, neither under the earth, was able to open the book, neither to look thereon.
4 And I wept much, because no man was found worthy to open and to read the book, neither to look thereon.
5 And one of the elders saith unto me, Weep not: behold, the Lion of the tribe of Juda, the Root of David, hath prevailed to open the book, and to loose the seven seals thereof.
C Jesus said: “But of that day or hour no man knoweth, neither the angels in heaven, nor the Son, but the Father.”
Hence, from a Biblical standpoint regarding the “time of the end”, it was not revealed to Daniel, nor to John the Revelator, nor even to the Son, Jesus.
This, in context, stands on its own merit. To disagree with that which is clearly written in the Bible concerning the matter must be taken up with God, not the Baha’is, for the Baha’is believe in God and the Bible.