Prayer is the means that God has appointed for receiving mercy and obtaining grace to help in time of need.
Hebrews 4:16 is one of the simplest and sweetest verses in the Bible, — “Let us therefore come boldly unto the throne of grace, that we may obtain mercy, and find grace to help in time of need.” These words make it very plain that God has appointed a way by which we shall seek and obtain mercy and grace. That way is prayer; bold, confident, outspoken approach to the throne of grace, the most holy place of God’s presence, where our sympathizing High Priest, Jesus Christ, has entered in our behalf. ( Verses 14 , 15 .)
Mercy is what we need, grace is what we must have, or all our life and effort will end in complete failure. Prayer is the way to get them. There is infinite grace at our disposal, and we make it ours experimentally by prayer. Oh, if we only realized the fullness of God’s grace, that is ours for the asking, its height and depth and length and breadth, I am sure that we would spend more time in prayer. The measure of our appropriation of grace is determined by the measure of our prayers.
Who is there that does not feel that he needs more grace? Then ask for it. Be constant and persistent in your asking. Be importunate and untiring in your asking. God delights to have us “shameless” beggars in this direction; for it shows our faith in Him, and He is mightily pleased with faith. Because of our “shamelessness” He will rise and give us as much as we need ( Luke 11:8 ).
-R.A. Torrey, How to Pray