The Ephraimites are sore because Jephthah defeated the Ammonites without them. Not that they wanted to fight, but they’re probably upset because a winning army received spoils from their victory. Jephthah points out to them that they were asked to help, and refused, so he went without them and won a victory, but now they’re acting tough when there’s nobody left to fight.
So because of this intertribal strife, there ends up being a battle at the Jordan river and when the Ephraimites try to cross they’re challenged with the word “shibboleth” and because of their inability to pronounce it correctly they gave themselves away and were killed. This episode is so famous that around the world, any phrase or word that is used as a mark to distinguish one group from another is called a shibboleth.
The religious leaders wanted to arrest him but they feared the people, because they knew he was talking about them when he told the parable of the wicked tenets. But instead of taking the meaning of this parable to heart they plow along and act it out exactly as it was in the parable. They send spies to pretend to be sincere in their questions in the hopes that they can get Jesus to trip up and do something to get him in trouble with the Romans, and then they’d be rid of the troublemaking rabbi from Galilee without dirtying their own hands.
After stumping the Pharisees with his answer to their tax trap, the Sadducees see an opportunity and so they jump in. They were a rival religious/political group to the Pharisees with some peculiar beliefs. They did not believe in the future resurrection, and so they present a trick question to Jesus about a woman who marries seven brothers because they keep dying without an heir, and then she dies. They want to know who’s wife she will be in the resurrection.
I can imagine they were snickering when they asked their question because they thought it was so clever, but Jesus deftly answered them by saying there’s no marriage in heaven, but he then pivots and shows them (using only the Pentateuch, because they reject all other scriptures) that the dead are not truly dead, and live on in God. This is also why we believe in the The Communion Of Saints.