Regarding sending forth righteous thoughts, Master has taught many times,
"As you know, the persecution that Dafa disciples in Mainland China suffer is quite severe, so each student has to truly, clearly realize what his responsibility is, and when he sends forth righteous thoughts he has to be able to truly calm his mind and truly produce the effect of righteous thoughts. So this is something extremely critical, extremely important. Then if every student is able to do that, I can tell you, with five minutes of sending forth righteous thoughts together, the evil in the Three Realms will never exist again--that's how important this is." ("Fa-Lecture at the Conference in Florida, U.S.A.")
"But that said, when Dafa disciples around the world send righteous thoughts together at the same time, the power is boundless. So, if each person had been able to handle this matter with very strong righteous thoughts and been doing it very well from the beginning, then perhaps there would be no evil remaining now. It's precisely because many practitioners have been interfered with by one thing or another that it hasn't been done well." ("Fa Teaching at the 2007 New York Fa Conference")
"Some Dafa disciples don't take sending righteous thoughts seriously, and not only are they themselves interfered with: Those wicked factors are interfering with other Dafa disciples as well. Can't you do well at what you are supposed to do? Not only must you do your own part well, but you should help others, too." ("Teaching the Fa in the City of Los Angeles")
"A lot of students don't place high importance on sending forth righteous thoughts, and a very big reason for this is that they are not sensitive [to what it is doing]. Whether you are sensitive or not, when Master tells you to do something you should do it, and it will for sure have its effect. It's definitely not just a formality!" ("Teaching the Fa in the City of Los Angeles")
From the above teachings, I came to understand that if we had done well in sending forth righteous thoughts, then either the evil would no longer exist or would have been eliminated to a very minute existence, and would no longer be capable of obstructing practitioners from saving sentient beings. But because many practitioners do not take sending forth righteous thoughts seriously, there remains a gap during all practitioners' collective sending forth of righteous thoughts. Thus, much of the evil can continue to live on in the dimensions that are the responsibility of these practitioners, continue to do bad things and prolong the persecution.
On the one hand, sending forth righteous thoughts is so critically important, but on the other hand, every time we collectively send forth righteous thoughts, there are always some practitioners who do not participate or do not participate well. I suggest that each and every Dafa practitioner take sending forth righteous thoughts seriously, and every time we collectively send forth righteous thoughts, try to prolong the duration. Practitioners who are in good states can use righteous thoughts to support those practitioners who can't participate for various reasons. They can also support those practitioners who are not in good states, so that there are no blank spots in our righteous field, thus eliminating the evil to the maximal extent. This will effectively eliminate one more portion of the evil, bringing the end of the persecution that much closer.
At the same time, I would like to remind fellow practitioners not to go to extremes. Taking sending forth righteous thoughts seriously does not equate to substituting it for Fa study and truth clarification. Taking sending forth righteous thoughts seriously should not be used as an excuse for not going out, or for covering up the attachment of fear. We must be responsible for our own cultivation and save sentient beings.