My favorite scripture in D&C is Section 93:1:
From D&C 93:1 we are given five requirements to see the Lord face to face. One of these is for us to ... "Calleth upon my name."
We call upon the name of Christ when we perform priesthood ordinances. When we bless others who stand in need. When testify in His name and when we close a prayer (always in His name or say Amen to these things.
Another way to "calleth on my name" is through mighty prayer.
I have found for me, that regular prayer will not bring about the blessings I desire. I needed to experience mighty prayer on a consistent basis. I know we have been taught "how to pray" but I have found that there are prayers and then there is Mighty prayer.
I know I used to pit all my petty interests first on my list to ask God. I would get bogged down on less important things that I had predetermined to be "of great worth" to me but I didn’t even think or desire what would Heavenly Father really want me to ask for instead. Getting outside myself and freeing up my mind to allow the Holy Spirit direct my prayers has had unbelievable results.
I decided to "Call upon His name" even that of Jesus Christ, our Lord while praying unto the Father. When prompted by the Holy Spirit to repent of mistakes that I needed to be forgiven of, The Spirit gave me the following to utter,"Heavenly Father, I call upon the name of Jesus Christ, thy Son, thine Only Begotten Son, that Thou mightest invite Him to thy throne so that he could act as my Advocate and Mediator. For Father, I am unworthy to receive any mercy or grace on my own. I ask that He, my Savior and Redeemer, might plead my case before Thee, for I have sinned and have need of forgiveness of my transgressions that I have stated before. I call upon His Name, even Jesus Christ, resting all my hope of receiving any mercy, grace, blessing or forgiveness solely upon His merits, upon His Atonement for which he has paid the price that justice demands and has bled from every pore and died upon the cross for my soul. Father, please allow my Savior to request mercy and forgiveness from Thee in my behalf." (When I had finished these words, I remained silent for few deep meditating moments and then I felt the power of the Holy Ghost fill my very soul and I knew that I had been forgiven completely).
Yes, Christ will be our Advocate and Mediator but we must ask it to be so. Ask and you shall receive. Remember we cannot assume anything. We need to know that our dear Savior stands, in our darkest hour of repentance, ready to plead our case before the Father. We are at that moment unworthy to approach the throne of God ourselves for no unclean thing can stand in His presence but He who knew no sin, who waits for our crying out and call to fill that void will be asked by the Father to approach that glorious throne and seek our forgiveness. This is another way we can Call upon His name.
Once the Holy Ghost had filled my soul, I forgot my list and allowed the Holy Ghost to fill my mind and heart, for He will speak in complete sentences to our hearts and our minds, (see D&C 8:2) for this is what the Lord meant by revealing heavenly things, "line upon line." (See D&C 98:12)
When we read a paragraph, we do so one line or sentence at a time. So the Holy Ghost will tell us in complete sentences, line upon line as to what we should pray about. Heavenly Father already knows all of our needs and what we are ready to receive through the Holy Ghost. "For, behold, the Comforter knoweth all things". (D&C 42:17) We want to have the Holy Ghost tell us what we should pray for because the Godhead desires to give us many things that we haven’t even thought of yet much less desired or expected. When the Holy Ghost tells you in your heart and in your mind what you really need to pray for, that is what the scriptures call mighty prayer. In D&C 50:29,30 the Lord makes clear that once we have been cleansed of all sin through the Holy Ghost, who is the purifier of our souls, when then will be given what we need to ask for and it shall be done. Are we willing to trust the Holy Ghost to guide us in mighty prayer or rely on our own understanding which we all know is flawed and short sighted?
Mighty prayer is the key we are is given when we have been cleansed of all sin to unlock the door to the mysteries of heaven.