A time-harmonic expansion of the gravitational tide potential is computed using an ephemeris of high precision for the Moon and the Sun and the latest I.A.U. astronomical constants. The results, which are computed for three different epochs and by novel methods, are compared with Doodson's classic expansion. The chief differences are due to secular trends in large terms and to revised constants which reduce all the solar terms. A new expansion is also given for the radiational tide potential.