Though I knew the name Meister Eckhardt, I had not read anything by him before that quote. It's an interesting thought, but I don't buy it.
I'll share from my experience that it really isn't a thought, or an idea, but rather it is a realization. It's something that becomes apparent as that Unity between yourself and the Divine occurs. It's a real experience, not an idea deduced by thinking about things you read. That state of Unity is something that opens understanding in ways beyond reasonings and speculations, into the very essence of being itself. And that essence is Light, Truth, Knowledge, Love, Compassion, Grace, and so forth. All that Eckhart was saying, and I concur with his words, is an expression of what is realized in that state of conscious awareness. The words are not theological in nature, but rather metaphorically expressive of a real experience of Reality.
I try (and usually fail) to be more like Jesus, but he was/is a historical person who lived, died and was physically resurrected (so the evidence convinces me), and I am not him.
We yes, I am not him either in the historical sense or his human identity.
But that same nature he realized in himself, is the same nature in you and me and everyone else. "Christ in you," the scripture explicitly states. There was to Jesus that dual nature of humanity and divinity. The same as us. "He that has seen me has seen the Father". It is incarnational.
As far as trying and failing... well yes. I'll share something that should help as you truly seek for that unity, to be like Christ. The trying and failing is what happens when we seek with our eye upon ourselves. When we seek because we are looking for something to fill a need in our lives, to make us happier, to take away this or that pain, because we feel weak and are seeking relief, etc, we are never truly doing what we need to which is to move beyond all those self-desiring needs.
It is in abandonment to God, to the Divine that we find what fulfills us. It is not in what we think we need that we begin our searching, but in the end of searching and in simply allowing. I'll put it this way, you should not seek to be like Jesus. You should simply open up and allow Christ. The seeking that we should do it to seek to not seek, to quit looking and start allowing. Our work, our struggle is to simply get out of the way and allow. Then it comes, and then you'll get what I mean in all of this.
I think we all do have a tiny spark of the divine in us, but that's not the same as being one with the creator and sustainer of the universe.
The one thing you find, that everyone who realizes this in themselves finds, is that it was always fully there the whole time. It only appears as a "spark" because that is all at the present we allow our minds to see, for fear it will overcome us. This is where the true meaning of faith comes in. It is to allow God in us, without fear. But you are right, there is a spark there you see, but that spark is the whole Universe in you.