Simple, just read the Bible, first we see the teaching method of Jesus according to the Bible is a very stern method and a method used by someone who claims to have authority.
Examples that I can find include:
Matthew 5:38 Ye have heard that it hath been said, An eye for an eye, and a tooth for a tooth:39But I say unto you, That ye resist not evil: but whosoever shall smite thee on thy right cheek, turn to him the other also.
Matthew 5:43 Ye have heard that it hath been said, Thou shalt love thy neighbour, and hate thine enemy. 44But I say unto you, Love your enemies, bless them that curse you, do good to them that hate you, and pray for them which despitefully use you, and persecute you;
Show the authority, where as teachers would say The Law says this and that, Jesus taught, "you heard this but I tell you that" and people quite naturally would have thought whose this geezer, and the hypocrites who wanted power would have been angry at this show of Authority.
Also, Jesus condemned the acts of many people, such as the comments of ‘When you pray do not be like the hypocrites, for they love to pray standing in the synagogues and on the street corners to be seen by others…’ (Matthew 6:5) It seems clear who Jesus is condemning, he went further on to say ‘..If God were your Father, you would love me, for I came from God and now am here. I have not come on my own; but he sent me. Why is my language not clear to you? Because you are unable to hear what I say. You belong to your father, the devil, and want to carry out your father’s desire...’ (John 8:42-44)
So from this point of anger it is clear that any chance came to get Jesus killed, so when Jesus says I and the father are one, the enemies jumped to the conclusion of claiming divinity just like a lot of Christians do, and when Jesus called himself son and so on they claimed he was making himself one with God. Yet if taken into context and from an unbiased party they would have seen differently.