“The effectual fervent prayer of a righteous man avails much”! ‘Effectual fervent’ means this is very powerful prayer. The Greek word often used for powerful is ‘dunamis’. We’ve borrowed this word into English as ‘dynamo’ (to generate electricity, power, to run your home, your car); and as ‘dynamite’ (a very unusual explosive which doesn’t waste its energy on the open air, but pushes the wall down, breaks open the rock face). So when we’re talking about prayer, your prayer must not be wasted on the air, but like dynamite, it must be dynamic enough to move the mountain out of the way! To move the sickness! To move the obstacle! If your prayer is not doing this, it’s not doing its job!