God is holy and his holiness consecrate everything, what is coming from him. His spirit same as everything we receive in a symbolic meaning, which represents Him. Therefore is important to consecrate ourselves, with repenting, that using of prayer materials can be effective.
God’s holiness
But you have come to Mount Zion, to the heavenly Jerusalem, the city of the living God. You have come to thousands upon thousands of angels in joyful assembly, to the church of the firstborn, whose names are written in heaven. You have come to God, the judge of all men, to the spirits of righteous men made perfect, to Jesus the mediator of a new covenant, and to the sprinkled blood that speaks a better word than the blood of Abel.
Hebrews 12;22-24
Who may ascend the hill of the Lord ? Who may stand in his holy place? He who has clean hands and a pure heart, who does not lift up his soul to an idol or swear by what is false.
Psalms 24;3-4
Sermons to this topic
​How to communicate to God