Verse 1: The results of action flow according to the law of the creator. Is Karma, action, God? It is insentient.
It is very simple: the karmas we have to pay for are such that good karmas have good fruit and bad karmas have bad fruit in our lives. Even of previous lives, we have to pay the results.
Verse 2: The fruits of are transient . Action causes one to fall into the ocean of further action. It obstructs the goal.
Comments: Shankrachary also described it very well in His Shankra Bhasha that, by Karma of every type, such as charity, feeding the people, so many types of good karma, liberation is not possible. Only meditation can liberate you. By good karma, you will go to higher loks, such as heaven.