'Sucklings' in the Bible

And Nob, the city of the priests, smote he with the edge of the sword, both men and women, children and sucklings, and oxen and asses and sheep, with the edge of the sword.

Out of the mouth of babes and sucklings hast thou established strength, Because of thine adversaries, That thou mightest still the enemy and the avenger.

Mine eyes do fail with tears, my heart is troubled; My liver is poured upon the earth, because of the destruction of the daughter of my people, Because the young children and the sucklings swoon in the streets of the city.

and said unto him, Hearest thou what these are saying? And Jesus saith unto them, Yea: did ye never read, Out of the mouth of babes and sucklings thou has perfected praise?