If he were riding on an ass, he dismounts (to pray). And if he cannot dismount, he turns his face [towards Jerusalem]. And if he cannot turn his face, he directs his heart to the Holy of Holies.
One should not rise to pray except with koved rosh (seriousness/gravity of thought). The early chasidim would wait one hour and then pray, in order to direct their hearts to the Place. Even if the king greets him (while he is praying), he may not answer him. And even if a snake is wound around his ankle he may not interrupt his prayer.
Rabbi Eliezer says: If one makes his prayer "fixed" [keva], his prayer is not considered supplication.
רבי אליעזר אומר כל העושה תפלתו קבע וכו׳: מאי קבע אמר רבי יעקב בר אידי אמר רבי אושעיא כל שתפלתו דומה עליו כמשוי ורבנן אמרי כל מי שאינו אומרה בלשון תחנונים רבה ורב יוסף דאמרי תרוייהו כל שאינו יכול לחדש בה דבר
We learned in the mishna that Rabbi Eliezer says: One whose prayer is fixed, his prayer is not supplication.
The Gemara asks: What is the meaning of fixed in this context?
Rabbi Ya’akov bar Idi said that Rabbi Oshaya said: It means anyone for whom his prayer is like a burden upon him.
The Rabbis say: This refers to anyone who does not recite prayer in the language of supplication.
Rabba and Rav Yosef both said: It refers to anyone unable to introduce a novel element.