Reference: Sharh ‘Umdatil-Fiqh – Tape No.8, Question No.34
Question: If someone wears a garment which shows some parts of his body from underneath, such as his thighs and shoulders, is his prayer [in that garment] correct?
Response: You mean it shows [some parts of his body] because of the tight-fitting garment and not because it is see-through? Either way it is impermissible to wear [any garment] which is tight-fitting and shows the outline of parts of his body, and likewise he must not wear [any garment which is] see-through which does not [suitably] cover his skin. So he should wear a garment which is loose-fitting and [suitably] covers [all the required parts of his body].