Law 3

  When one object exerts a force on another object, the second exerts a force on the first that is equal in magnitude and opposite in direction

  If you try to accelerate a ball by kicking it, your foot will feel the equal force the ball is exerting on you. If you exert a force on a baseball to stop it, the ball also exerts a force on you.
  If you exert a small force on the ball, it exerts a small force on you. Th larger the force you exert on the ball, the stronger it's force on you. The magnitudes are always equal.