Not entire sure what a 'jubah' is, but this pattern is one that I have seen in a variety of middle eastern clothing. And it looks damn comfy so I will likely end up making at least one of these for myself.
Here is how you make this elegant but sophisticated and simple T shirt. I used silk charmeuse but you can use basically any shirting weight fabric. It will fit and flatter any body type and size. All you need is 1 yard of fabric and about 2 hours to make this sweet T! Please note, silk is harder to sew, so if you are a beginner I suggest using cotton fabric.