Moving a piece out of the way for check I was recently told you may not move a piece out of the way of a second piece to allow the second piece to put the other player in check.  For example, I have my queen and rook lined up on a diagonal with my opponent's king.  I move my rook, opening the path for my queen to their king putting it in check.  According to my opponent, you aren't allowed to do this. You have to actively move the queen into a check position.

Is this a standard rule?
You can move your other piece to make your queen attack the king in a normal position such as:

4r3/8/8/2QB1k2/p5q1/3K4/8/8 w - - 0 1

1.Bf3+**[Discovered-Check]
(1.Be4+**[Double-check])




But you are forbidden to do so if the piece you move will put your own king in check, such as: 

3r4/8/8/2QB1k2/p5q1/3K4/8/8 w - - 0 1

1.Bf3**[illegal-move] 


Here both Be4 and Bf3 are illegal because the rook on d8 will be attacking your King.

So to conclude, there is no standard rule avoiding you to play discovered check except when the move puts your own king in check.