32 Moreover, those who pray should not come to God with fruitless or naked prayers. Petition is ineffectual when it is a barren entreaty that beseeches God. For as every tree that brings not forth fruit is cut down and cast into the fire; assuredly also, words that do not bear fruit cannot deserve anything of God, because they are fruitful in no result. And thus Holy Scripture instructs us, saying, “Prayer is good with fasting and almsgiving.” For He who will give us in the day of judgment a reward for our labours and alms, is even in this life a merciful hearer of one who comes to Him in prayer associated with good works. Thus, for instance, Cornelius the centurion, when he prayed, had a claim to be heard. For he was in the habit of doing many almsdeeds towards the people, and of ever praying to God. To this man, when he prayed about the ninth hour, appeared an angel bearing testimony to his labours, and saying, “Cornelius, your prayers and your alms are gone up in remembrance before God.”
Source: The Treatises of Cyprian (New Advent)