To answer the questions it is necessary to acknowledge there are three main problems that make this verse incomprehensible as it currently stands.
The source text is corrupt, the better text can be found in the Codex Bezae available at the University of Cambridge Digital Library.
Translation suffers because of the first point, i will explain that.
One should read the whole sequence from Mark 10:17-31 to understand it better.
- In Codex Bezae we read a different text:
αποκριθεις δε ο ιης αμην λεγω ϋμειν ουδεις εστιν ος αφηκεν η
αδελφους η αδελφας η μητερα η τεκνα η αγρους ενεκεν εμου η ενεκα του
ευαγγελιου · ος αν μη λαβη εκατονταπλασιονα εν τω καιρω τουτω ος δε
αφηκεν οικειαν και αδελφας και αδελφους και μητερα και τεκνα και
αγρους μετα διωγμου · εν τω αιωνι τω ερχομενω ζωην αιωνιον λημψεται
By traditional translation it would render something like this:
“Truly I tell you,” Jesus replied, “no one who has left home or brothers or sisters or mother or children or fields for my sake or for the gospel who will fail to receive a hundredfold in the appropriate time, but who has left houses and brothers and sisters and mothers and children and fields along with persecution, will receive in the age to come eternal life.
Here Jesus differentiates two categories of followers, those who leave everything for the sake of him and the gospel and those that do so with persecution.
That seems to make even less sense than in our traditional translated story.
- Well, the solution to that problem is in the translation, to begin with that of διωγμου. The noun comes from the verb διώκω and while that can also be translated as physically pursue, it is quite often used in Greek to convey eager pursuit of a desired result. You can use it as in pursuit of love, happiness, or wealth. The LSJ Greek-English lexicon even mentions τὰ πλούτου δίωγμα, eager pursuit of wealth, as an example and i think that is meant here too. The corruption of the text caused later translators to miss the context completely so they resorted to a default of physical persecution.
Another word that needs reappraisal is ζωή which is not biological life as such but more the way or means of living, it can even mean the property one needs to make a living.
Furthermore we should take note that λαμβάνω, here often translated as receive can also have the more active meaning of take, grasp or hold on to.
Next we have αἰών and αἰῶνος habitually translated as age and eternal but that translation falls short here too and is even a bit silly, there is no such thing as eternal human life. The translation of αἰών is in fact a natural lifetime and within such a lifetime αἰῶνος would be just always, or all your remaining life. In the same light one can translate the question of the rich man in Mark 10:17 as
"What should I do in order to inherit the means to live for the rest
of my life?"
The answer Jesus provides is in fact pragmatic, the command to honour your mother and father is the real clincher here because in order to let the natural order of things play out it would be unwise to antagonize your own father if one wants to inherit. That it has nothing to do with eternal life is confirmed in Deuteronomy 5:16 where this paraphrase originates and there is just a promise of a long life to enjoy the land that your Lord and God is giving you, and He is only doing so by the natural order of things that a father dies before the son so he can inherit. God gave the land to the fathers and the sons will inherit if they keep the commandments their fathers taught them.
- One should read the whole preceding chapter and observe that the kingdom of God is not about receiving wealth, on the contrary, one should renounce wealth as a precondition to be able to enter the kingdom of God. Mark 10:23-25 even emphatically says:
23Then Jesus looked around and said to His disciples, “How hard it is
for the rich to enter the kingdom of God!” 24And the disciples were
amazed at His words. But Jesus said to them again, “Children, how hard
it is for those who trust in riches to enter the kingdom of God! 25It
is easier for a camel to pass through the eye of a needle than for a
rich man to enter the kingdom of God.”…
In that context we can translate the fate of the second category Jesus mentioned in verse 10:30 as follows:
but who has left houses and brothers and sisters and mothers and
children and fields in order to pursue gain, will always hold on to
property for the rest of his life.
So in the light of the mentioned difficulty to enter the kingdom of God for those that trust in riches, this category will never enter the kingdom of God.
The whole talk about a hundredfold reception of houses, brothers, sisters, mothers, children, and fields is an ironic hyperbole and should not be taken as a literal promise or prophecy of a reward, it is addressed at Peter who showed his impatient greed in his question in Mark 10:28:
Peter began to say to Him, “Look, we have left everything and followed You.”
and it ridicules him, he didn't even leave behind his house, nor his brothers or sisters within, and while he has no children we know of, even if he had left a child, does one even want a hundred children, or even more ridiculous a hundred mothers? He is a poor fisherman, he didn't even own fields so how could he have left those behind?
To top it of there is also the juxtaposition of ἀκολουθέω(verse 28) and διώκω(verse 30) applied. Peter says we followed you loyally, Jesus says he did it only for personal gain. It is all irony.
And the following verse Mark 10:31 can now be adequately explained as another ironic remark about those two categories of followers Jesus mentioned.
"But many who are first will be last, and the last will be first.”
It should be read as the number of people in the first category will be few/insignificant, and those in the last will be many/prominent.
Jesus holds no illusions about the proper motivation of his disciples, as we have seen all through the gospel of Mark. He might be right, they are shown to be greedy, envious, self-serving dimwits.