Chapter 90 in Tehillim is part of the Pesukay D'Zimra on Shabbos. This is the, "Prayer of Moshe". What was Moshe's prayer about? Is this a prayer that Moshe wrote for the Jews in exile? Or is this a prayer for the dedication of the Mishkan? What can we learn from this chapter of Tehillim about Avodad Hashem? Chapter 91 in Tehillim is also part of the Pesukay D'Zimra on Shabbos. What is the theme of this chapter of Tehillim?