well, thats why the grace of god is so..."easy", because the standard has been raised and we need it.
keep in mind the context though, when he referenced this it was according to their deeds as the crowds would have understood what he was saying. Jesus wasn't validating their religious hearts, but rather, their zeal to accomplish such intense obedience. so, unless your righteousness (zeal for doing whats right) surpasses that of the pharisees, you will not enter the kingdom. in this case, true, authentic zeal fueled by the love of God in your heart. this is also why he says "if you love me you'll keep my commandments" that is not saying because you do them that proves you love him. it is saying, in essence, if you fall head over heels in love with god, then you'll obey him without even trying. its like a married couple. you don't kiss your wife because you're married and you have to (at least, i hope not), you do it because you love her. If i have to tell you to love your wife then there is a problem...hope that helped clear up what i was trying to say.
And also those who don't love Him will not keep His commandments--
23 Jesus replied, “Anyone who loves me will obey my teaching. My Father will love them, and we will come to them and make our home with them.
24 Anyone who does not love me will not obey my teaching. These words you hear are not my own; they belong to the Father who sent me."
This reminds us of how "by their fruits you will know them". And
Matthew 7:18 A good tree cannot bear bad fruit, and a bad tree cannot bear good fruit.
But going just a little further we run into the sharp and very emphasized teaching He said to you and me in verses 21 through 27.
Consider: He is speaking as if there will be moments when you have to choose, between 2 paths. Of course, we all stumble at times, and can confess, and be cleansed and restored (1 John chapter 1). But there is the continued and repeated emphasis from our Teacher, our Redeemer, Christ Jesus, that we need (at times) to remember to choose His way, His path for us --
"But everyone who hears these words of mine and does not put them into practice is like a foolish man who built his house on sand.
27 The rain came down, the streams rose, and the winds blew and beat against that house, and it fell with a great crash.”
Of course, He didn't say empty words to no purpose here, but is talking to believers, you and I, and telling us something so crucial, about what finally will allow us to endure, or be destroyed, in the end, by the storms of life, whether our faith will endure. As Paul wrote it in Romans chapter 8, we have to choose to walk in the spirit instead of in the flesh.
So while you are totally right it's the most natural response to Christ, our Savoir, to do as He said to do, to love, it's still at times of temptation that there are 2 choices, and at those moments, having 2 attractions, 2 things pulling at us, His way and the pull of the flesh, then suddenly we really do have to remember His words, or look to Him.
Of course, one can pray the prayer He gave you and me to pray in Matthew 6 -- that we not be led into temptation, but that we be delivered from evil. This prayer aids so much. While I find that looking to Christ helps me immensely to love all my neighbors and to forgive, still it aids us much to be helped against temptations. These words of His to us in the gospels are invaluable for our daily lives.