the needle you use must be (usable) with the thread you are using- needle size and thread size/weight are dependent on each other- the wrong needle with the thread will cause fraying/breakage/tension problems/uneven stitching...just to name a few issues.
if you visit a thread site (like superior threads they offer free charts that tell you what needle and size you should use with each different type/weight of thread- it is an invaluable chart.