Luke 9:50

48 And He said to them, “Whoever welcomes this little child in My name welcomes Me, and whoever welcomes Me welcomes the One who sent Me. For whoever is the least among all of you, he is the greatest.”

49 “Master,” said John, “we saw someone driving out demons in Your name, and we tried to stop him, because he does not accompany us.”

“Do not stop him,” Jesus replied, “for whoever is not against you is for you.”

51 As the day of His ascension approached, Jesus resolutely set out for Jerusalem.

52 He sent messengers on ahead, who went into a village of the Samaritans to make arrangements for Him.

Do read the surrounding verses too, because the context often says more than a single verse.

Compare

BSB
“Do not stop him,” Jesus replied, “for whoever is not against you is for you.”
KJV
And Jesus said unto him, Forbid him not: for he that is not against us is for us.
WEB
Jesus said to him, “Don’t forbid him, for he who is not against us is for us.”
ASV
But Jesus said unto him, Forbid [him] not: for he that is not against you is for you.
DARBY
And Jesus said to him, Forbid [him] not, for he that is not against you is for you.
BLB
And Jesus said to him, “Do not forbid [it]; for whoever is not against you⁺ is for you⁺.”
ÅB
Og Jesus sa til ham: Forbyd det ikke! for den som ikke er imot dere, er med dere.
OTB
"Ikke stopp ham," sa Jesus, "for den som ikke er imot dere, er for dere."
B1930
Og Jesus sa til ham: Forbyd det ikke! for den som ikke er imot eder, er med eder.

Study notes (Tyndale)

Original text and word study

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