riddle - Harnessed by the 6th day

I am the redeemer, the primal desire

I destroy what I can, yet in such I can heal.

I tear down all I touch, yet lift up the flier

I'm the servant of men, yet commander of steel.

What am I?

Answer

Are you

Fire?

I am the redeemer, the primal desire

Cavemen+fire

I destroy what I can, yet in such I can heal.

It burns what it touches but you can use it to cauterize wounds.

I tear down all I touch, yet lift up the flier

Forest fires or hot air balloons

I'm the servant of men, yet commander of steel.

You can forge steel in fire, but people make fire for their own purpose.