Theoretically could celestial warping occur with multiple significant masses? My knowledge of physics and math is limited but I find it fascinating. After reading some books on astronomy and physics I learnt about celestial warping of light caused by the warping of space-time which had me thinking:
Theoretically, could celestial warping occur with multiple significant masses (white dwarfs) so that the light emitted by an object (star) is observed in front of us when it is actually behind (relatively speaking)?
If this is the case then could an observer essentially view the light from the object on opposite sides of the earth? 
I have drawn a crude diagram to try and explain what I am talking about.

 A: Yes, in principle this is possible. If the masses were massive enough and arranged in exactly the right positions, you might be able to see two copies of the object on opposite sides of the Earth. However, there are many caveats. First, because the arrangement for this kind of multiple lensing needs to be quite precise, this is extremely unlikely to ever happen, and if it does, it is extremely unlikely to last any amount of time (especially since objects that are massive enough to make this work will almost certainly have significant mutual gravitational attraction). Second, the lensed copy of the object would most likely be quite dim; after all, only a fraction of the incident light is lensed in the right direction, and this happens with every mass in the chain, so more masses makes the final brightness exponentially smaller. Third, the final lensed image is likely to be severely distorted, and may not even be recognizable at the end.
A: The amount of deflection of light (for a given mass) depends on how close the ray of light passes to the center of star.  Light which barely skims the star's surface has the maximum deflection, limited by the radius of the star.
There is a plot here showing that you have to get within a few hundred kilometers of the center of a star to get even 1 degree of deflection.
A white dwarf, which is the mass of a star compressed to the size of a planet, does not have enough gravitational field at its surface to bend light very much.  You would need thousands of white dwarfs arranged just right to turn light all the way back to you.
For a neutron star, the mass of a star compressed to the size of a city, each pass of light just skimming the surface will be deflected maybe a few tens of degrees.  You could probably get away with perfectly aligning less than a dozen of these.  Still beyond the current state of practice for celestial engineering.
A black hole, on the other hand, lets the light get close enough to the surface that light from you can come in and do a hairpin turn and come out right at you.  In fact, you can use light that gets even closer to the event horizon which makes one-and-a-half turns and come back to you. Closer still, 2,3,..100... and a half turns are possible, and all of those come back to you.
So, as is usually the case, a black hole is the only practical solution to your problem.
A: Gravitational lenses have a poor image quality. They stretch the image of a point source into a thin curved line. This is especially true in your setup where you can use the ligh passed only on one side of each heavy mass (unless you use a single black hole to turn light around 180 degrees, in which case the starlight would form a thin circle around the black hole). While conceptually you could warp a small portion of light all the way around, what you would get is an extremely faint, stretched and highly distorted image that would be hard to detect or recognize as starlight. However, if you do know the exact locations and masses of all the heavy objects that bend the light of the star, then you could build a computer model using the equations of General Relativity to refocus the distorted image, as shown here, where of course light was bent on a smaller angle.


