"'Your beginning will seem humble, so prosperous will your future be.'" NIV translation
Bildad continues to give advice to Job and, here, it seems like he is giving Job some encouragement and what he says is actually going to happen as we will see in the end. The problem with what Bildad is saying is that he is linking earthly wealth and prosperity with righteousness.
Bildad's relatives had probably passed down this method of evaluating someone's relationship with God. To him, it was pretty cut and dried that a poor man sitting on a pile of trash could not possibly "be right with God".
The same sort of thing goes on today even among Christians and this tradition is what is known as the "prosperity gospel". This is basically the same thing that Bildad was telling Job that, if you are right with God, then, you will have everything that your heart desires.
Once again, Job's friends are so focused on the physical that they have no insight into the spiritual. They are looking at "the fruits of the world" or lack of it instead of looking for the "fruits of the Spirit" to determine someone's status with God. You can possess all that the world has to offer (fruits of the world) and yet not have a right relationship with God but you cannot have the fruits of the Spirit without that relationship.
"'Ask the former generation and find out what their ancestors learned, for we were born only yesterday and know nothing, and our days on earth are but a shadow.'" NIV translation
Bildad appeals to Job to look at the knowledge that has been accumulated and passed down through the years. He acknowledges that a single man does not have sufficient time on this earth to learn everything but believes that each generation builds on the wisdom of the former. This may seem like it is all well and good and it is but only to a point. We learn more and more as we build on what has been revealed to others but it is limited especially when it comes to the things of God. We can learn facts from the past but to know God it must be due to a personal experience.