Obviously I’m quoting something, and we don’t usually say “stayed”.
Let me first comment on the most common use of the word “stay”, and then apply the full quotation from the title.

“Stay” is a universal command by dog owners to tell their dogs to stay where they are until instructed otherwise.
And “stay” is universally learned and obeyed by ‘man’s best friend’ because they trust and want to please their master.

The command to stay is in a separate category from the other common words of instruction that are taught to dogs.
Sit, come, fetch, roll over—all involve action on the dog’s part.
Stay—that often calls for something more in the relationship between dog and master, something that may call for long-term obedience, something that may not include understanding why—that calls for trust.
Stay—trust—waiting—doing nothing—focused.

My border collie, Buddy, is close to fourteen (a rescue at one), and in our long time together we’ve grown very close, and continue getting closer.
I appreciate him more, and I thank God for him often, and we understand each other in new ways as we both experience our senior years.

Trust—in Buddy’s younger years trust was demonstrated hundreds of times when I had to leave him at the front gate a quarter mile from the house.
As I got out of my van to open the gate, Buddy was always filled with hope that he might go along to my job.
If I just said the magic word “with” (part of the line “Buddy, want to go with me?”), he exploded and headed for the van door.
But most of the time (and more so now as he is older) I had to tell him, “I have to go, and you have to stay.”
Then, when I got out of my van to close the gate, I told him the same thing again, he accepted it, and I knelt down and hugged him and talked to him with an extended, endearing good-by ritual.

Many times Buddy was sitting at the gate when I came home.
Other times he would recognize the sound of my van half a mile away and meet me at the gate when I drove up.
But the ultimate faithfulness, which breaks my heart, is the report of times that Buddy “stayed” at that gate all day in cold rain, waiting for me.

That I don’t deserve—and it compels me to make it up to him any way I can, greeting him heartily and massaging him just the way he likes.
Buddy’s heart of trust and faithfulness is as strong as ever, but his body is not.
He has to be close to me, and he still gets up and follows me whenever I go to another room or out the door.
He often stands at the door and watches to see where I am going, and accepts my words again, “Buddy, I have to go, and you have to stay.”

Buddy still likes to run, even though his back legs collapse sometimes now from a life-threatening injury years ago, with a miracle recovery, and he joins me if he can when I’m working at the front of our place.
We used to take Buddy lots of places in stores and restaurants as my ‘service dog’, and it hurts now when people ask, “Where’s Buddy?”
One of these days they’ll ask, “Where’s Larry?” (Or maybe they won’t.)
In either case, it moves me to appreciate the blessings of time and strength and work, and dogs—Buddy, Miles, Goodness, and Mercy.

– – –

And now, to apply the quotation from the title of this article—
“You will keep him in perfect peace, whose mind is stayed on You . . .”

The capitalized “You” gives it away, that we’re talking about God—stayed on Him, just like my faithful dog, Buddy.
When a devoted dog stays, especially for an extended time, it is much more than obedience—the relationship with the master consumes everything he has to offer.
The same with us and God—obedience is very important, but when He sees our mind focused, stayed, on Him, then He keeps us in perfect peace WHILE WE WAIT, even for an extended time.

Perfect peace—mind stayed on God—stay and wait.
Open your Bible and find a ton of verses on waiting.
Some to get you started:

“Be still, and know that I am God.”

“They that wait upon the Lord shall renew their strength; they shall mount up with wings like eagles, they shall run and not be weary, they shall walk and not faint.” (That’s good for youth, middle age, senior, just like Buddy and me.)

“What is required of us . . . to be found faithful.”

“Be faithful unto death, and I will give you a crown of life.”

“Trust in the Lord with all your heart . . .”

In the middle of writing this, Buddy walks in to my office (75 feet from the house), and I greet him enthusiastically and massage him, and he lies down one foot from my chair.
I think that’s what God wants from us, often.

And now, the rest of the verse:
“You will keep him in perfect peace, whose mind is stayed on You, because he trusts in You.”

Please read MY GOOD BUDDY AND MIRACLE MILES — type in the search bar on this site.

If you can find it, get an inspiring little hardback book about another Border Collie.
LESSONS FROM A SHEEPDOG—–Phillip Keller (true story)

“In his weakness, Paul became a receptacle for the power of God, that he could not know otherwise.”
—–David Jeremiah