Most of these parallels are distinctive as they are unique to these two chapters and are not found elsewhere in Tanakh.1 Their concentration bolsters the contention that David's song is meant to hark back to Channah's prayer.
It is possible that David's song comes to answer the major question left open by Channah's prayer. Who is the "מַלְכּוֹ" and "מְשִׁיחוֹ" to which Channah refers (see also the discussion in Channah's Prayer)? The settling of this question is the focus of the entire book of Shemuel. For the first part of the book, the reader wonders whether the answer is Shaul, and he is even referred to as "מְשִׁיחַ ה'".2 It is only at the end of the book that the concluding verse of David's song "מִגְדּוֹל יְשׁוּעוֹת מַלְכּוֹ וְעֹשֶׂה חֶסֶד לִמְשִׁיחוֹ לְדָוִד וּלְזַרְעוֹ עַד עוֹלָם" provides the ultimate answer to this question. Thus, David's song provides closure to Channah's prayer and the entire book of Shemuel.