Philippians 2:14-16

Do all things without murmurings and disputings: That ye may be blameless and harmless, the sons of God, without rebuke, in the midst of a crooked and perverse nation, among whom ye shine as lights in the world; Holding forth the word of life; that I may rejoice in the day of Christ, that I have not run in vain, neither laboured in vain.

John 6:41-43

The Jews then murmured at him, because he said, I am the bread which came down from heaven. And they said, Is not this Jesus, the son of Joseph, whose father and mother we know? how is it then that he saith, I came down from heaven? Jesus therefore answered and said unto them, Murmur not among yourselves.