I will kneel upon my knees and spread my hands to the Lord God.This description of prayer is interesting because, with one exception, it matches depictions of prayer in pictures surviving from the ancient world. It was typical to depict people praying standing with hands stretched apart and lifted up to heaven. What is different about Ezra's description is that he is kneeling.
The position of prayer is something of a cultural thing. In Egypt, the hands would face in for prayers of petition and face outward for prayers of praise. In Mesopotamia, the position of prayer was either with the hands uplifted or with the hand touching the nose. In modern times, a variety of positions are used depending on cultural or religious preference: palms together, or hands clasped, or arms folded, sometimes kneeling. The exact position might be cultural, but assuming a position is important. As C. S. Lewis has his devil Screwtape explain:
One of their poets, Coleridge, has recorded that he did not pray "with moving lips and bended knees" but merely "composed his spirit to love" and indulged "a sense of supplication." That is exactly the sort of prayer we want; and since it bears a superficial resemblance to the prayer of silence as practised by those who are very far advanced in the Enemy's service, clever and lazy patients can be taken in by it for quite a long time. At the very least, they can be persuaded that the bodily position makes no difference to their prayers; for they constantly forget, what you must always remember, that they are animals and that whatever their bodies do affects their souls. (C. S. Lewis, The Screwtape Letters, chapter 4).So while the exact form may be culturally determined, for most of us, it cannot be dispensed with altogether.