The Laws of Prayer (79)

1. In the blessing of “Retzeih” we say “and the fire offerings of Klal Yisrael… You shall willingly accept!”, and even though nowadays there is no sacrificial service, we are asking that our prayers which are replacing the offerings should be accepted willingly before Hashem. (Mishne Berurah 120)

2. If one is coming to bow down at the places where one is supposed to bow, and one finds spittle in one’s mouth, one should not bow down until one has removed the spittle from one’s mouth. (ibid)