(Clearwisdom.net) This is my personal understanding. It may not be complete, but I wrote it down for your reference.
First Requirement for Fa-rectification Practitioners: Their Hearts are Devoted to Saving People
In "Practicing Only One Cultivation Way" in Lecture Three of Zhuan Falun Master said,
"...no matter how high or how low my level is, I am among everyday people and still doing something purposeful--that is saving people--and my heart is devoted to saving people." (Zhuan Falun, 2000)
Therefore, Fa-rectification practitioners, no matter where you are, at work or while doing daily things, in our hearts we should always be thinking of saving people. This is what Master wants us to do as much as possible. Whether we are walking, working, eating, or sleeping, the part of us that is different from all other people is that, in our hearts, we are always thinking of how to save people, what method to use, how to fully use the gifts that we have accumulated throughout our lives. Then we will wisely and rationally grasp all the chances we come across to save people and clarify the truth.
Master says, "If you do not stop a murder or arson, what would you get involved with?" (Zhuan Falun, 2000). In this present period of time, the evil persecuting practitioners is not just murder or arson. People's minds have been poisoned by the evil propaganda; its effects are already totally beyond imagination. When we face people, how can we remain unfeeling, how can our hearts not think of saving them? If we do not, then there must be a problem. We have to fulfill this obligation in this lifetime: the reason why we came here is for Dafa. We need to put our whole heart into saving people and clarifying the truth to them. We have no time to waste. We cannot behave like everyday people; we should know what we should do. Fa-rectification Dafa practitioners should put their hearts into saving people, because that is the main reason why we are here today. So, how could anything shake our righteous hearts?
Second Requirement for Fa-rectification Practitioners: Their Thoughts Stay in the Fa at All Times
In "The Issue of Eating Meat" in Zhuan Falun Master said,
"Because our practice is one in which the Fa cultivates practitioners, this means that some situations will arise from gong and the Fa."
The universal law explained in this book is the only way for us to be able to ascend beyond the old universe and be rectified. Therefore, if our thoughts are not on the Fa, aren't we in the old principles? Everything in the new universe is unknown to the sentient beings in the old universe. Fa-rectification Dafa practitioners' thoughts must be in the Fa so that the thoughts manifested meet the requirement of Fa-rectification, which is also the requirement of the new universe. The Fa cultivates practitioners. This practice is all automatic, so we will know what to do from the Fa.
Fa-rectification Dafa practitioner's thoughts must contain the Fa, therefore, we have to learn the Fa and use all of our extra time to study and recite the Fa. Many practitioners sleep only a few hours every day, and reading two or three lectures a day is not too much for them. Dafa can do everything as long as our mind always stays in the Fa. Many things we do are beyond what an everyday person can do. Fa-rectification Dafa practitioners are really doing magnificent and divine deeds.