D&C 84:20-21: Therefore, in the aordinances [of the Priesthood], the power of bgodlinessis manifest. And without the ordinances thereof, and the aauthority of the priesthood, the power of godliness is bnot manifest unto men in the flesh.
Personally, I could never make sense of this scripture. I knew it was important, but I really wasn't sure what the Lord was getting at; I always assumed it meant something like feeling the Spirit really strongly when you participate in ordinances, but that didn't seem to be the answer. Well, the Dallas East Stake President, President Larsen, visited the Dallas 5th Ward for Ward Conference and explained this scripture to the elders and high priests of the ward. He explained that through the ordinances of the Priesthood, truly miraculous things happen that can only be done by the power of God. When we are baptized, are sins are washed away. When we receive the Gift of the Holy Ghost, we receive the right to his constant companionship. When we are sealed in the temple, we are bound by the power and authority of God to those we love for all eternity. If that isn't the power of godliness made manifest, I don't know what is. I realized these ordinances are essential for our process of conversion and becoming more and more like our Heavenly Father.
For example: I remember very clearly our first visit with Jason Quinteros after his baptism. We had visited with him in his house more times than I could count, and we had definitely felt the Spirit there before; but we went in after immediately after he had received the Gift of the Holy Ghost, I noticed right away that the "vib" of the house had changed. The Spirit was already there when we came in. Soon into our conversation with Jason's father, Elder Trujillo said to him, "Your house feels different you know." I was surprised, because I hadn't commented anything to him. I have no doubt that was a direct effect of Jason's decision to worthily participate in the ordinances of the priesthood.
I've come to develop a strong testimony of the true power of Priesthood ordinances--they are real, and in the "power of godliness is manifest." It is only through that authority, worthily exercised, that we can receive the full blessings of the Atonement of Jesus Christ. I testify that that is true, and that is why it is important that we share this message with everyone who is willing to listen.