Generally, because we begin our lives immersed in water in the womb, when we dream of water and water-related objects it can represent our spirituality, our essence and soul – the root of our life and all life.
An oar in a dream can represent control and direction through the water, guiding our soul and steering our way along our spiritual course.
However, manipulating oars to row efficiently, in waking life, requires a certain amount of skill or proficiency, so this implement could represent difficulties in navigating our spirituality, especially if we’re handling oars clumsily and ineptly.
Of course, you may be masterfully controlling the oars in your dream, in which case it could be suggesting your current path in life is the right one to choose.
Still, it may be that you aren’t using the oar for its intended purpose, i.e rowing, but are wielding it like a weapon. This could represent a need to get control of your own destiny by grabbing the oar and taking control.