The Jews sought to kill Jesus after He healed the man at the pool of Bethesda because they thought that He

A.

Claimed to have authority to forgive sins

B.

Made Himself equal with God

C.

Did not agree with the law of Moses

D.

Said that He was born before Abraham

Correct answer is B

John 5:18 
Therefore the Jews sought all the more to kill Him, because He not only broke the Sabbath, but also said that God was His Father, making Himself equal with God.