The exercise of the powers granted by this chapter shall be in all respects for the benefit of the inhabitants of the Commonwealth and for the promotion of their safety, health, welfare, convenience and prosperity. The operation and maintenance of any hospital project which the authority is authorized to undertake will constitute the performance of an essential governmental function; therefore, the authority shall not be required to pay any taxes or assessments upon any hospital project acquired or constructed by it. The bonds issued under the provisions of this chapter, their transfer and the income therefrom, including any profit made on the sale thereof, shall at all times be free and exempt from taxation by the Commonwealth and any political subdivision thereof.