Why does a star appear to rise 4 min earlier in the Sky every night than the Previous night?

It is due to the orbit of the Sun.It is all with respect to Sun's position by which we calculate the time daily.Earth's Orbit and rotation is both Anti Clockwise .So as it orbits the Sun,on each successive night,it is oriented slightly more to the east than it was the Night before.
By the time Earth goes around its Axis once, It has moved in its orbit by almost 1°. The stars appears at the same angle ,but compared to the Sun's position,it is shifted by 1°.
If 360° takes 24 hours(to rotate)for a degree it takes ,
   24hours / 360°
= 1 hour / 15°
= 60 min / 15°
= 4 min / 1°
this is Sideral day.(Sideral day is 4 minutes faster than Earth's Usual day ,24 hours).This is the reason that a particular star will rise 4 minutes earlier every night.

For example , Star Spica :
Date.             Rise.             Set.
May 1,2020        5:26 P.M            5:11 A.M
May 2,2020        5:22 P.M            5:07 A.M
May 3,2020        5:18 P.M            5:03 A.M
May 4,2020        5:14 P.M            4:59 A.M
May 5,2020        5:10 P.M            4:55 A.M


                                         -PVGANIGA