The three who were killed had been forced to kneel in a prayer position while assassins shot each in the forehead.
As the conclave draws to a close, each cardinal will approach the new pope and kneel before him.
As he went to kneel, I took a shot at him and [he] jumped in the door.
Old English cneowlian, from cneow (see knee (n.)); cf. Middle Low German knelen, Middle Dutch cnielen, Dutch knielen Gothic knussjan. Past tense knelt is a modern formation (19c.) on analogy of feel/felt, etc. Related: Kneeling.