Especially now, Li An's power of time has grown enough to influence many things; it is no longer just the few thousand years' worth of power that, to heaven and earth, was merely a drop in the ocean, not worth mentioning.
If he were to use this technique to kill enemies or to disrupt heaven and earth, he would not be tolerated by the heavens. He would have to, by his own strength, resist the power of the entire current world's time and space... This would likely require paying with his life.
He is strong, but definitely not to the point where he can resist the power of an entire era by himself.
After all, the essence of time he absorbs is merely the remnants from past eras, mere imprints of less than one in a hundred from those epochs. If there were ever a day when he could truly absorb an entire complete time and space, then his power of time might have a gleam of hope to rival the present heaven and earth.
