You know those collages of pictures where each picture is a theme, maybe families, maybe in black and white; but as you stand back you see the BIG picture created by all of them? Well this is why a young earth is what the bible teaches. God starts off the book with 7 days of creation, but this is the zoomed in view.
There are 7,000 years of time given in the bible, and in 2nd Peter 3:8, Peter wrote: "But, beloved, be not ignorant of this one thing, that one day is with the Lord as a thousand years, and a thousand years as one day." So each 1000 years is one day with the 1000 year Sabbath at the end.
The 7 days of creation mirror the 7,000 years of the Bible. On the first 2 days God divided light and darkness. But isn't this what happened at the flood? After 2,000 years The flood happened, and the 3rd day/millennium started, and dry land formed. The SUN is created on the 4th day, and in the 4th millennium Jesus is born. The 5th and 6th days are all animals with souls "For the life of the flesh is in the blood" Lev 17:11. At the end of the 6th day man is created, which mirrors the promise of redeemed bodies before the Day of the Lord. And finally on the 7th day God rested, and in the millennium, we rest.
To believe that the bible is the word of God, is to believe the whole picture, and young earth is what it shows. And by that standard we should hold what the world tells us up to that light. In other words, I believe God first.
...the great dragon was cast out, that serpent of old, called the Devil and Satan, who deceives the whole world. Rev 12:9