In this article, we will demonstrate, based upon strictly logical reasoning, thought experiment examination, and cosmic observations results, how gravitational time dilation exerts influences upon light propagation and upon gravity propagation. Neutron stars mergers have shown that the speed of gravity coincides with the speed of light (c). However, does gravitational time dilation has the same effect upon the propagation of gravity field as it has on light/electric field/magnetic field? The answer to this question can be concluded by examining such a thought experiment: according to E=mc2, it is theoretically possible to transfer an enormous amount of energy to a place near a black hole and create some matter. Once created, the matter will start to generate both gravity field and light and the gravity field and light will propagate in each direction. The light it generates will NEVER enter into the black hole so it will never interact with the black hole, according to observers on the earth. But, according to current cosmic observation results, the gravity field it generates will quickly enter into the black hole and interact with the black hole, according to observers on the earth. Thus, if gravitational time dilation theory is correct, near a black hole, gravity speed is faster than light speed.