Some argue that the Bible is contradictory concerning who arrested Jesus, whether it was the crowd or the romans. The argument is that John 18:12 says that the Romans arrested Jesus, but Matthew 26:47, 50, Mark 14:43, and Luke 22:47 say that the crowd came the arrest Jesus. However, the solution to this alleged contradiction is extremely simple.
While he was still speaking, Judas came, one of the twelve, and with him a great crowd with swords and clubs, from the chief priests and the elders of the people… 50 Jesus said to him, “Friend, do what you came to do.” Then they came up and laid hands on Jesus and seized him.Matthew 26:47, 50
And immediately, while he was still speaking, Judas came, one of the twelve, and with him a crowd with swords and clubs, from the chief priests and the scribes and the elders.Mark 14:43
While he was still speaking, there came a crowd, and the man called Judas, one of the twelve, was leading them. He drew near to Jesus to kiss him,Luke 22:47
So the band of soldiers and their captain and the officers of the Jews arrested Jesus and bound him.John 18:12
The simple explanation for this alleged contradiction is that the crowd of people that came included the Romans, and it was the Romans who arrested Jesus. John is simply being more specific than Matthew, Mark, and Luke.
To read more answers to alleged and apparent contradictions in the Bible, see “Contradictions” in the Bible Answered.
These books are also excellent resources: