Halakhah zu Bereschit 1:14

The meaning of “was empty and void” (“tohu vavohu”) (Genesis 1:2) is that it contained neither man nor animal. As Jeremiah explains, “I saw the land and it was empty and void (tohu vavohu)” (4:23), for which he explains the meaning afterward by saying, “I saw and there was no man” (ibid. 4:25) nor “animal” (ibid. 9:9). Similarly, “like the light of the seven days” (Isaiah 30:26) is an explanation of “sevenfold” (ibid.). Also, “that which I will be” (Exodus 3:14) explains “I will be” (ibid.). I have already explained the mystery of “sevenfold.”¹⁶ In his Alternative Commentary to Genesis (1:14), Ibn Ezra explains that the light increasingly intensified over the seven days of Creation, hence “sevenfold” means that there were seven stages to the light. Our Rabbis hinted at this when they said that on the fourth day the luminaries were hung (Hagiga 12a). How admirable to the intelligent is the choice of the word “hung.”¹⁷ The description of Creation in the book of Genesis deals only with creation of the lower world, the world of generation and decay, and it does not expound on the creation of the heavenly bodies. So all Scripture tells us about the heavenly bodies is that they were “hung” and visible to the lower world. Thus the words of Jeremiah disprove those who say that “tohu vavohu” means that there was no earth.

Birkat ha-Hammah is a blessing praising God, "who makes the work of creation" and is recited on the occasion of the return of the sun to the position in the heavens which it occupied at the moment of its original creation when that event occurs on the day of the week and at the hour of the day which correspond to the day and hour of the creation of the sun. Genesis 1:14-19 records that the sun was created on the fourth day of the week. According to rabbinic tradition the sun was created at the very beginning of the day and was affixed in the sky in the position occupied at Tekufat Nisan, i.e., the vernal equinox. Thus Birkat ha-Hammah is recited whenever the vernal equinox occurs at the very beginning of the fourth day of the week. At the time of the equinox day and night are equal in duration, each being twelve hours in length. Since in the Jewish calendar each day begins with nightfall the beginning of the fourth day is 6:00 P.M. Tuesday evening.