it is impossible
to explain to one who has not experienced it, but i will attempt anyway.
one can enter a state of zen when there is no physical break between thought, action, and consequence.
there is a zen of pinball, when the paddles become direct extensions of your brain, and you no longer feel the little buttons on the side of the machine, nor the spring as you let loose another ball. there is a zen of music, although it is one of the hardest to reach. music takes so much concentration to maintain that it is hard to simply lose one's self. when you're not playing the music, it is possible, but then you are not actively creating. the zen of programming is truly strange. it requires that your fingers don't have to move a long way--any taint of physical thought takes you farther from perfection. this zen is when your program becomes a direct extension of your brain, and you know it all, in detail and in general. your fingers are no longer thought about. they are as quick and as accurate as the mercurial movement of masterful music, when no break exists between player and listener, nor between note and note.
the zen of love has all these qualities, but is far above them all. while all of these link a brain to an object, love links brain to brain, and what could be better? a musician cannot beam his notes to his audience; a programmer cannot write his code with a single thought; but a lover feels his beloved as himself, no break between the physical reality of a kiss and the mental blast of pure emotion that travels through it. a writer's words must be thought about, contemplated; though they may come quickly at times, the writer will always stumble at a phrase, and not be able to finish it. in love, "you will know your action. you are present there, not thinking of somewhere else you ought to be." your heart and that of yours are one. what can parallel this intensity? i say, nothing.