Why Tehillim, Chapter 29 is considered to be the basis of the prayer?

  Thank you

The nineteenth bracha of the “Amidah” is hinted to by the Name G-d (in the 3d verse of this chapter).

The words “the Voice of Hashem” are repeated seven times in this psalm – corresponding to the seven brachos in the “Amidah” of Shabbat, the seventh day of Creation.