1)
What is the significance of "Karavta b'Yom Ekra'echa"?
1.
Rashi: In the early days, You would come close to me on days that I called You.
2.
Ibn Ezra: Even before I found You, You were close when I called to You.
3.
Ri Kara: E.g. in Egypt I called and Your answered. "Va'Ye'anchu Vnei Yisrael Min ha'Avodah va'Yiz'aku
2)
When did Hashem say "Al Tira'u"?
1.
Ri Kara: Whenever I used to call to You, You called to me, "and You said 'do not fear.'"
2.
Palgei Mayim: At the sea, You said "Al Tira'u" (Shemos 14:13). These verses hint to Galus Mitzrayim, and the coming verses to Galus Bavel and Madai.