People often ask: how should we pray, in what words, and in what language? Some even say: “I do not pray because I do not know how; I do not know any prayers.” You do not need any specialized skill for prayer. You can simply talk to God. Many Orthodox Churches across the world use a special language in the divine services, such as Church Slavonic or Koine Greek. But in private prayer, when we are alone with God, there is no need for any special language. We can pray to God in the language we use when speaking with people, when thinking.
Prayer should be very simple. St. Isaac the Syrian said:
The whole fabric of your prayer should be succinct. One word saved the publican, and one word made the thief on the cross heir to the heavenly kingdom.
Prayer can be extremely brief. If you are just starting out on your path to prayer, begin with very short prayers, such as can allow you to focus. God does not need words; he needs men’s hearts. Words are secondary; of paramount importance are the feeling and disposition with which we approach God. To approach God without a feeling of reverence or with distraction—when during prayer our mind wanders—is much more dangerous than saying the wrong words in prayer. Distracted prayer has neither meaning nor value. A simple law is at work: if the words of prayer do not reach our heart, they will not reach God. As it is sometimes put, such prayer does not reach above the ceiling of the room in which we are praying, and it should reach the heavens. Therefore it is very important that each word of prayer should be felt deeply by us. If you are incapable of focusing on the long prayers contained in the prayer books of the Orthodox Church, try your hand at shorter prayers:
Lord, have mercy.
Lord, help me.
God, have mercy on me, the sinner.
One ascetic struggler said that if we could, with the full force of our feelings—with all our heart and soul—just say the prayer “Lord, have mercy,” then that would be enough for salvation. But the problem is that, as a rule, we cannot say this with all our heart; we cannot say this with all our whole life. Therefore, in order to be heard by God, we tend to use many words.
Let us remember that God longs for our hearts, not for our words. If we turn to him with our whole hearts, then we will certainly get a response.
Excerpt from Prayer: Encounter with the Living God by His Eminence Metropolitan Hilarion (Alfeyev). Emphases added.