Atah Hu Adonai L'Vadecha is a series of verses recited during Shacharit

Shacharit

Shacharit is the the daily morning Tefillah of the Jewish people, one of the three times there is prayer each day.Shacharit is said to have been established by the patriarch Abraham when he prayed in the morning...

, the morning prayers of Judaism

Judaism

Judaism ) is the "religion, philosophy, and way of life" of the Jewish people...

, in pesukei dezimra. It is composed of verses 6-11 in Chapter 9 of Nechemiah

Book of Nehemiah

The Book of Nehemiah is a book of the Hebrew Bible. Told largely in the form of a first-person memoir, it concerns the rebuilding of the walls of Jerusalem by Nehemiah, a Jew who is a high official at the Persian court, and the dedication of the city and its people to God's laws...

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The recitation of these verses was introduced in the 13th century by Rabbi Meir of Rothenburg

Meir of Rothenburg

Meir of Rothenburg was a German Rabbi and poet, a major author of the tosafot on Rashi's commentary on the Talmud...

. The custom to recite these verses, along with Vayivarech David

Vayivarech David

Vayivarech David is a prayer recited during Shacharit in pesukei dezimra. It is composed of Verses 10-13 of Chapter 29 from Chronicles Book I....

 (from Chronicles) prior to the Song of the sea

Song of the sea

The Song of the Sea is a poem that appears in the Book of Exodus of the Hebrew Bible, at . It is followed in verses 20 and 21 by a much shorter song sung by Miriam and the other women...

 is to recall miracles brough on by G-d at the Red Sea

Red Sea

The Red Sea is a seawater inlet of the Indian Ocean, lying between Africa and Asia. The connection to the ocean is in the south through the Bab el Mandeb strait and the Gulf of Aden. In the north, there is the Sinai Peninsula, the Gulf of Aqaba, and the Gulf of Suez...

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In most siddurim, this prayer appears as two separate paragraphs. What is interesting about this division is not the mere division, but that the split occurs in the middle of the third verse (Nechemiah 9:8). This is signifying Abraham

Abraham

Abraham , whose birth name was Abram, is the eponym of the Abrahamic religions, among which are Judaism, Christianity and Islam...

's change of name from Abram to Abraham, elevating his status from the father of Aram to the father of a multitude of nations.