When oil and lye are combined and heated, the result is soap. This chemical reaction is called saponification. Without lye, saponification isn’t possible, so lye is necessary to create soap.
The Rate of formation of products depends on the concentration of reactants or the forward reaction increases on increasing the rate of the concentration.
There is no effect on the equilibrium rate when the concentration of reactants and products is constant.
Forward reaction slows down when the reactant concentration is decreased.
On increasing the amount or concentration of reactant the chemical equilibrium shifts towards formation of more products.