What will the church at Thyatira get for overcoming?

An iron rod to smash the nations and the morning star

To the angel of the church in Thyatira write ...

And he that overcometh, and keepeth my works unto the end, to him will I give power over the nations:

And he shall rule them with a rod of iron; as the vessels of a potter shall they be broken to shivers: even as I received of my Father.

And I will give him the morning star. Revelation 2:18, 26-28