1)
Why does it say "Yachel Yisrael El Hashem"?
1.
Radak: With these Midos, conduct with lowliness covertly and openly, and do not raise your heart to wonders. Hope to Hashem, and He will fulfill your hope!
2.
Malbim: Hashem is the one who teaches and conducts Yisrael like a mother to her children.
2)
Why does it say "me'Atah v'Ad Olam"?
1.
Radak: Hashem will fulfill your hope forever.
2.
Malbim: An infant looks to his mother only in his youth, but Yisrael hope to Hashem forever.