I really like the book Taking Hold of God. It endeavors to incite believers to pray by showcasing the faithfulness of a number of Reformed and Puritan brothers from history.
There is a chapter on Matthew Henry that I have found very helpful and convicting. Here is a sample:
Henry wrote in his diary, ‘I love prayer. It is that which buckles on all the Christain’s armour.’ Since the Christian must wear God’s armor at all times, he must pray without ceasing. According to Henry, the access that Christians have to God in Christ gives them:
(1) A companion ready in all their solitudes, so that they are never less alone than when alone. Do we need better society than fellowship with the Father?
(2) A counsellor ready in all their doubts,…a guide (Ps. 73:24), who has promised to direct with his eye, to lead us in the way wherein we should go.
(3) A comforter ready in all their sorrows…[to] support sinking spirits, and be the strength of a fainting heart.
(4) A supply ready in all their wants. They that have access to God have access to a full fountain, an inexhaustible treasure, a rich mine.
(5) A support ready under all their burdens. They have access to him asAdonai [my Lord], my stay and the strength of my heart (Ps. 73:26).
(6) A shelter ready in all their dangers, a city of refuge near at hand. The name of the Lord is a strong tower (Prov. 18:10).
(7) Strength ready for all their performances in doing work, fighting work. He is their arm every morning (Isa. 33:2).
(8) Salvation insured by a sweet and undeceiving earnest…If he thus guides us by his counsel he will receive us to glory.
Good stuff.
