I remember, many years ago at the first retreat I ever attended with Reb Zalman z"l, hearing him talk about prayer* -- specifically about the sense one might have, at a certain point, that the words have all already been said. If one is taking on a daily (or even weekly) prayer practice, there will likely come a time when one has the feeling: I've said all of this already. Does God really need to hear this again?
But prayer isn't that kind of communication. It's like saying "I love you." Imagine that one were to say to one's beloved "I love you" -- would one's beloved respond with "eh, who cares, you said that already"? Of course not. The point of saying "I love you" is not merely conveying intellectual data. The point of saying "I love you" is creating, or rekindling, a connection on the level of the heart.
When we pray, when we engage in any kind of devotional practice, in a sense we're saying I love You to God. Ultimately it's not about the words we use or the information we're communicating. What matters is what's happening in our hearts. (And, the mystical tradition teaches, also therefore in the heart of the Holy One of Blessing. When we offer love to God, we stimulate the flow of love in return.)
Anytime I say "I love you," if I'm saying the words with intention, I'm speaking to the spark of divinity which enlivens that person -- the nitzotz elohut, the spark of godliness in that soul.
When I say "I love you" to a beloved, I'm also saying it to God. That's true whether the words emerge out of deep conversation, or whether I'm texting a shorthand ILU from my phone to theirs.
Here too the analogy between connecting with my human beloveds and my Divine Beloved holds true. Holiness is in the place of connection between I and Thou, even if that connection is brief.
There are times when I manage only snatches or snippets of regular prayer, which might as well be text messages from me to the Divine. What makes those short texts to God work is the fact that they're part of an ongoing conversation.
Any time I open my siddur, or sing lines of liturgy while driving the car, or open my heart to ask for a change I wish I could see in the world, I can feel the connection open. Every time I talk to God is "to be continued," because the conversation is never really over.
And I know that what matters is not whether I'm using "the right" words or whether I'm saying something I've never said before. What matters is that I'm saying it from the heart. When I speak from my heart, when I really mean my words, something in me opens. And if I have the feeling that you received (or You received) the words the way I meant them, then the connection between us can bloom.
*I had been absolutely convinced that I remembered Reb Zalman saying this about prayer. And then I went to look back in my retreat notes from the retreat where I was pretty sure he said it... and it turns out he said it about Torah, instead! I still offer this teaching in his honor.