He is simply stating that the Sift which is to be received is the Holy Ghost Himself. This is the route for all of us when becoming Christians. One of the problems of confusion about the work of the Holy Spirit is that we have a tendency to identify Him with some subsequent work of grace after one is saved. God promises that believers become partakers in the divine nature. Having received the Holy Spirit and being born into God's family, a very simple question needs to be answered.
Some people believe it is just to make the individual feel good.
But that can hardly be the reason. Others think they are saved just to go to Heaven, but that is not the primary reason because that will come when life is ended. The only answer that fits the Bible teaching is that we are saved to serve here and now. To put it very simply, I was created to fulfill the purpose and plan of God now. That's why I wasn't born one thousand years ago.