But for those who have not attained the capability of praying sincerely it is necessary to pray slowly, waiting for a corresponding echo in the heart to each word of the prayer. And this is not always soon given to men unaccustomed to prayerful contemplation. Therefore, for such men, it must be laid down as an absolute rule to pronounce the words of the prayer slowly, and with pauses. Wait until every word gives back its corresponding echo in your heart.
–Saint John of Kronstadt (1829-1908)