1)
What is the meaning of "You are Elokim"?
1.
Rashi: You rule, and You have ability to fulfill. Malbim citing Mahari - he needed to say so, lest people say that that he prayed so much because he doubted Hashem's ability or the prophecy of His Navi.
2)
What is the meaning of "u'Devarecha Yihyu Emes"?
1.
Radak: This was a prayer [that Your words be fulfilled].
2.
Radak citing Targum Yonasan: Your words are true.
3.
Malbim: It is impossible that there will be any change from Your side. He admitted to the truth of the Nevu'ah said to him.
