For John Calvin, prayer was like a priceless treasure that God has offered to His people.
Calvin’s first rule of prayer was to enter into it with a full awareness of the One to whom we are speaking. The key to prayer is a spirit of reverence and adoration: “Let the first rule of right prayer be, to have our heart and mind framed as becomes those who are entering into converse with God.”
Calvin wrote of how easy it is for our minds to wander in prayer. We become inattentive, as if we were speaking to someone with whom we are easily bored. This insults the glory of God: “Let us know, then, that none duly prepare themselves [sic] for prayer but those who are so impressed with the majesty of God that they engage in it free from all earthly cares and affections.”
Calvin’s second rule of prayer was that we ask only for those things that God permits. Prayer can be an exercise in blasphemy if we entreat His blessing for our sinful desires: “I lately observed, men in prayer give greater license to their unlawful desires than if they were telling jocular tales among their equals.”