It is good for the saints to draw near to God; it is not only good because it is their duty, but because it yields their souls a spiritual pleasure; and it is also of great profit and advantage to them: It is often an ordinance of God, and which he owns for the quickening the graces of his spirit, for the restraining and subduing the corruptions of our hearts, and for the bringing of our souls into nearer communion and fellowship with himself. Satan has often felt the force and power of this piece of our spiritual armour; and it is, indeed, the last which the believer is directed to make use of. Praying souls are profitable in families, neighbourhoods, churches, and common-wealths, when prayerless ones are in a great measure useless. The believer has the utmost encouragement to this work he can desire; he may come to God, not as on a seat of justice, but as on a throne of grace. Christ is the Mediator between God and him, his way of access to God, and his Advocate with the Father; the Spirit is his Guide, Director, and Assister; he has many exceeding great and precious promises to plead with God; nor need he doubt of a kind reception, a gracious audience, and a proper answer, though never so mean and unworthy in himself; since the Lord will regard the prayer of the destitute, and not despise his prayer.
John Gill (1697-1771) on Prayer