Completion, fulfilment or ending?

I'm trying to understand Jesus' attitude to the Law.
Matthew portrays Jesus as a new Moses, and Moses' great gift to Israel was the Law.
So what is Jesus doing? Is he bringing a new Law? Is he getting rid of Law altogether? What respect does he have for that most fundamental and precious part of Jewish life, the thing that made them distinct from every other people?
It's captured in one Greek word, plerosai.
Jesus says, "Don't think that I've come to abolish the Law & the Prophets. I haven't come to abolish them, I've come to plerosai them."
The word means "to fill," and is usually translated "fulfil." I haven't come to abolish the law, I've come to fulfil it. So does that mean we should still keep the law?
When you are filling a pot with water, you carry on pouring until it is full, then you stop.
So shall we stop keeping the law?

Perhaps the question should be, what are we keeping it for?
Jesus was emphatic in saying that the law will not pass away. He goes on to say repeatedly, "You have heard it was said, 'Do this,' but I say to you, 'Do that.'" Where 'that' is even harder and more stringent than 'this.'
So he is raising the bar.
Jesus seems to be asking for more than basic obedience, more than doing "just enough." Speed limits are imposed on drivers as a safety measure, and simply not breaking the speed limit doesn't necessarily mean you are driving safely. If you drive along at 29 miles per hour, but with your eyes closed, you might be keeping the letter of the law in terms of not breaking the speed limit, but you are not keeping the spirit of the law which is to encourage you to drive safely.
On the other hand, Jesus seems to be implying that just the letter of the law won't do. So if you even think about speeding, one day a telepathic speed camera might hand you a summons.
How can anybody keep laws this stringent?
Maybe that's the point.
As Jesus says - "Unless your righteousness surpasses that of the pharisees ... you will certainly not enter the kingdom of heaven."

Don't rely on keeping the law to fit you for heaven. We are going to need something else entirely to make us acceptable in God's eyes.
Something, or someone else.