This is why Jesus came and made the Old Testament standard even more impossible to accomplish: To get us to give up trying: To level the field and put every one of us on equal footing. For centuries the Jews had worked very hard to live up to everything the law of Moses commanded them to be and do (according to their generally self-serving interpretation of what Moses wrote), and the end result was a whole lot of pride and self-centeredness and cruelty to others rather than a heart cry for God’s mercy and grace for everybody: A few powerful people made themselves look good by making everybody else look bad.
So Jesus deliberately said that in order to be holy by God’s standard we had to live the same kind of life that He Himself lived. He said that even if we think about a sinful act (e.g. fantasizing about a night with some centerfold goddess or soap-opera hunk) , we are as guilty of sexual sin as we would be if we’d had our dream come true, even though our lusts were limited only to our imagination. He made righteousness by our own efforts obviously impossible (as impossible for Mother Theresa as for the sickest serial killer), not so that He could mock our efforts, but rather so that we would be compelled to come to God on entirely different terms, and would stop lying to ourselves about the truth of our lostness and our profound need for the Grace and Mercy of our Father and Lord. (Until we admit we are lost, we cannot begin the process of getting un-lost: Remember the fights your dad and mom had out in the middle of some nowhere because he was driving and wouldn’t admit that he needed to ask directions? Well, our spiritual condition is much the same, but with enormously more dire consequences.) If you read the accounts of Jesus’ life, you will realize that He set the standard impossibly high. The Bible says, simply, that He never sinned...period. Jesus lived in perfect fellowship with and obedience and service to His Father, drawing His strength from the Holy Spirit whose presence never left Him. The Old Testament standard was a cakewalk compared to the example demonstrated by Jesus for 33 years, and then commanded of all of us by Jesus Himself (Matthew 5:48): Competition becomes pointless when it is obvious to all that nobody can ever win without help: The Pope and the pimp stand side by side. And Jesus says to all of us that, rather than working to get into Heaven on our own merits, which we can never succeed in doing, we can become one of His friends and followers, and together we will walk into Heaven because He belongs there and we’re with Him.