If it happens on the line, it’s a clear penalty, so if it happens in the box, the same applies. His hand in a unnatural position stopped the ball, going to another player in a goal scoring or advanced position.
The player stops a forward attacking pass to another attacking player (who has created space) with his arm in an unnatural angle. He should not be pointing at another player and this is completely irrelevant anyway, it’s a clearcut penalty. What happens if the pliayer is on the line pointing to the goalkeeper to save it, and it stops it going in the net by hitting his arm?