When mind and heart are united in prayer and the soul is wholly concentrated in a single desire for God, then the heart grows warm and the light of Christ begins to shine and fills the inward man with peace and joy. We should thank the Lord for everything and give ourselves up to His will; we should also offer Him all our thoughts and words, and strive to make everything serve only His good pleasure.

St. Seraphim of Sarov

St. Seraphim’s statement points us to prayer with attention. Uniting heart and mind is the very core of praying with attention. It may well be that this is done with difficulty and only for a short period of time. But such directed union with Christ is deeply beneficial to our lives. Here is a description of St. Seraphim’s “Little Rule of Prayer” from the site Orthodoxphotos. I might add that there is much helpful material on this site as well as the photos.

How to Pray When time is Short
Which words to use when praying? What should one do, who does not have enough memory, who through lack of learning did not learn the most important prayers, and finally, those (and this life situation does occur) when there is simply not enough time to stand before the icons and read the compulsory morning and evening prayers? This question was decided by the great elder Seraphim of Sarov. Many visitors of the elder faulted themselves for praying very little, that they did not read even the mandated morning and evening prayers.

St. Seraphim established for such people the following easily accomplished rule:

“Upon rising from sleep, let each Christian, standing before the holy icons, read the prayer “Our Father” thrice, in honor of the Most Holy Trinity. Then the song of the Mother of God: “Rejoice, O Virgin Theotokos Mary, full of grace…” also thrice. In conclusion the Creed: “I believe…” — once. Completing such a rule, let each Orthodox engage in his duties, to which he is assigned or called. During his work at home or along the way anywhere he should quietly read “Lord Jesus Christ, have mercy upon me, a sinner,” but if others surround him, then, while busy with his duties, let him only say in his mind “Lord, have mercy,” — and thus until lunch. Right before lunch let him repeat the morning rule. After lunch, busy with his work, let every Christian read just as quietly: “Most Holy Mother of God, save me, a sinner.” When preparing for sleep, let every Christian again read the morning rule, i.e., “Our Father” thrice, “Rejoice, O Virgin Theotokos Mary” thrice and once “I believe.”

St. Seraphim explained that, keeping to this small “rule,” one can attain a measure of Christian perfection, because these three prayers — are the foundation of Christianity. The first, as the prayer given by the Lord Himself, is the pattern for all prayers. The second is brought from Heaven by the
Archangel upon greeting the Mother of God. The Creed contains in itself all the salutary dogmas of the Christian faith.

In addition the elder counseled reading the Jesus prayer during activities, while walking, even in bed, and as confirmation used the following words from the letters to the Romans: “For whosoever shall call upon the name of the Lord shall be saved” (Rom. 10: 13). For those who have time, the elder suggested reading the Gospel, canons, akathists, psalms.