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Why does a catalyst accelerate both the forward and reverse reactions?

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nanoparticles: hydrogen peroxide — catalysis Nanoparticles of a gold-palladium (yellow-blue) alloy supported on acid-treated carbon (gray) directly catalyzing hydrogen peroxide formation from hydrogen (white) and oxygen (red) while shutting off unwanted hydrogen peroxide decomposition.

A catalyst accelerates both the forward and reverse reactions because a reverse chemical reaction proceeds by the reversal of the specific steps that constitute the mechanism of the forward reaction. By lowering the activation energy required for a reaction to occur, a catalyst facilitates the transformation of reactants into products and products back into reactants with equal efficiency.1

Because the catalyst affects both directions of the reaction equally, it does not alter the position of chemical equilibrium; rather, it only increases the rate at which that equilibrium is attained. This process is consistent with the principle of microscopic reversibility, which dictates that at equilibrium, the rates of the forward and backward reactions are equal.123