These forms of asking for forgiveness have evolved in the Asian countries over centuries but when done with a pure intention they can free the mind from worry or remorse and prepare it for meditation or for making a big step in one's life like ordination etc. Traditionally also there formulas are used:
ukāsa vandāmi bhante
sabbam aparādham khamatha me bhante
mayā katam puññam sāminā anumoditabbam
sāminā katam puññam mayham dātabbam
sādhu sādhu anumodāmi.http://webcache.googleusercontent.com/s ... google.com
Ukāsa, dvāra-tayena kataṃ, sabbaṃ apāradhaṃ khamatu no (me) bhante.
We (I) ask your leave. We (I) ask you to forgive us (me) for whatever wrong we (I) have done with the three doors (of body, speech, & mind).
Vandāmi bhante cetiyaṃ, sabbaṃ sabbattha ṭhāne, supatiṭṭhitaṃ sārīraṅka-dhātuṃ, mahā-bodhiṃ buddha-rūpaṃ, sakkāratthaṃ.
I revere every stupa established in every place, every Relic of the Buddha's body, every Great Bodhi tree, every Buddha image that is an object of veneration.
Ahaṃ vandāmi dhātuyo, ahaṃ vandāmi sabbaso, iccetaṃ ratana-tayaṃ, ahaṃ vandāmi sabbadā.
I revere the relics. I revere them everywhere. I always revere the Triple Gem.http://www.dhammatalks.org/dhamma/chanting/verses2.htm
Kāyena vācā cittena
Pamādena mayā katam
Accayam khama me bhante
15. Forgiveness of Faults
If by deeds, speech or thoughts heedlessly
I have committed any wrong-doing
Forgive me, O Venerable,
O Victor, Greatly Wise!http://www.buddhismotheravada.it/16.html