Personal preference aside, there are key differences to these two cleansers.
Body washes gained popularity in the 80's and 90's, but recently bar soaps have made a come back, particularly natural, hand-crafted soaps.
Large production commercial body washes are primarily composed of water and surfactants, like sodium laureate sulfate, sodium laurel sulfate, and other chemicals. Although these products can appear silky, pearly and creamy looking, surfactants can strip the skin of its natural oils, leaving it dehydrated, dry and tight.
In the past, bar soaps got a bad rap for their high PH, however, well-crafted soaps are made with skin-loving saponified oils of olive, sunflower, coconut, etc. These excellent naturally sulfate-free cleansers blended with nourishing ingredients such as Shea Butter, and Aloe Vera creates a product that is balanced, moisturizing, and great for most skin types, including Psoriasis and Eczema.
One of my favorite properties about hand made bar soaps is how superior they are at exfoliating and removing dead skin cells. You know the dreaded "soap scum" that annoys us so much? Well, that happens when using bar soaps versus store body washes because the base ingredients used to create hand crafted soaps naturally exfoliate and remove more dead skin cells than watered down commercial body washes. To me, that healthier skin is worth a bit of rinsing of the tub or shower.
Whatever your preference, remember, soap kills germs, bacteria and many viruses. Wash your hands often to keep skin clean, and follow with a healthy, plant-based moisturizer to keep your skin hydrated.