Fourth Day

God created sun on forth day but with out sun how four days gone?

Jewish understanding of the universe is given below . They thought that the earth is round and flat , not globe as we know it today . They thought that the sun , moon and stars are fixed in the firmament or within the frame work the sun moves from one corner (end ) to another ( end ). According to them the earth is at the centre of the universe. They didn't know about the solar system and the planetary motions. We interpret the Genesis 1st chapter according to the knowledge we have now. They interpreted it according to their knowledge based on their belief system. They didn't know  about the 24 hours a day calculation as we do it  now .  When God began to create the heaven and the earth , the first thing He  created was Light. We can call this light as " Cosmic Light" or  "Light in the whole Universe." Secondly God separated the water by firmament . Water above the firmament and water below the firmament and the waters gathered at the lowest places and formed sea.Third God created the plants , trees etc., Fourth God placed or fixed the sun , moon and stars to give light to the earth in day and night times and to calculate days and nights , and to know  the seasons . According to my understanding , this is something like construction of a house , when we build a house we will do a work one by one . After building a house we will fix lights in each room . For over all work we may use a bigger light for the construction of the house from the beginning itself . So before the beginning of the creation work God created a cosmic light. After fixing the sun , moon and stars in the firmament ,God created the  solar light . The day given in the Gen 1 st chapter is not 24 hours time period  , its duration may be from 12 hours to 1000 years or even more than that . Every work of God on the creation day  list is  separated by a phrase called  "evening and morning." Referrence : Twentieth Century Bible Commentary edited by G.Henton Davies , Alan Richardson and Charles L.Wallis ( photo from this book)  & The Teacher's Bible Commentary edited  by H.Franklin Paschall and Herschel H. Hobbs.