Nephi says, in effect, "I perceive that you’re still pondering these things in your heart and you really haven’t bought into all of this, you’re still worried or wondering or puzzling about it, and this grieves me." Pondering usually involves some kind of weighing and balancing, or halting between two opinions. Pondering can be a good thing, if it doesn’t become paralyzing. Moroni 10:3 invites people to ponder when they receive the Book of Mormon. But Moroni and Nephi both expect that pondering will lead to prayer and to asking God (Moroni 10:4). The solution for Nephi is also to pray. He wants his people to pray more often, so apparently this has become a problem in their little community. It is reminiscent of what the Lord says to the Brother of Jared, "Hey, it’s been a while since you’ve checked in with me."
So Nephi says, "For if ye would hearken unto the Spirit which teacheth a man to pray, ye would know that ye must pray; for the evil spirit teacheth not a man to pray, but teacheth him that he must not pray." Prayer is crucial for what we do. Nephi emphasizes that with what he says next, that we must pray before we perform anything to the Lord. "But behold, I say unto you that ye must pray always, and not faint; that ye must not perform any thing unto the Lord save in the first place ye shall pray unto the Father in the name of Christ, that he will consecrate thy performance unto thee, that thy performance may be for the welfare of thy soul."
We need to stop, pause, and pray. If we do not do this, our actions cannot be elevated to the level of being consecrated to the Lord, and that is something that will bless us deliberately. There is no limit on the occasions when we need to do this, for anything that we do unto the Lord needs to be dedicated unto him. Otherwise, we are just doing it, and that action will not have the same effect or yield the same results.
Book of Mormon Central, "Why Must One Pray Always to Endure to the End? (2 Nephi 32:8-9)," KnoWhy 298 (April 10, 2017).