Marine pipe laying systems and methods including a hoisting device for laying an offshore pipeline are disclosed. The hoisting device includes a tower with a tower top side provided with cable pulleys and a moveable traveling block displaceably attached to the tower. The traveling block includes first and second blocks with cable pulleys. A clamp attaches to the first block for holding pipe sections and lowering pipelines after the pipe section connects to the pipeline. The hoisting device includes a hoisting means including hoisting cable and a winch. The hoisting cable can be guided over the cable pulleys on the tower and the traveling block. The first and second blocks are adapted to be releasably coupled for traveling along the tower as a unit and for supporting greater pipeline weights. The second block can be locked to the tower to remain stationary while the first block travels along the tower.