Twitter follower "Sarah" wrote to the Gladiator Oscar winner, "Heard about your separation today. I said a prayer for you and your family".
The 48-year-old responded, "Hey Sarah, that was very kind of you. Thank you for your thoughts".
Russell followed it up by re-tweeting a post by his screenwriter friend Mark Staufer.
"This morning I’m sending out positive connective energy to any dads who are separated from the kids they love," read the tweet.
It's the first time the Gladiator Oscar winner has commented on the split and missing his children, who are living in Sydney with Danielle.
Russell is currently filming Darren Aronofsky's biblical epic Noah in New York, and has spent most of the year apart from his kids working back-to-back on The Man with the Iron Fists, Broken City, Les Misérables, and Man of Steel.
The Kiwi-born actor also hit back at Twitter trolls posting nasty messages.
"Hey haters ... Every min[ute] you are harassing me is another min[ute] you are distracted from spewing hate at people who are less resolute. Haha, God bless," Russell wrote.
A commenter had earlier written that Russell "put himself first, not @SpencerDanielle and his kids Charles and Tennyson. He makes bad choices".
Mark responded, "Such insight from someone who doesn't exist, has never met any of the people involved, and purports to love Christ. #bless".
You don't want to mess with Russell Crowe check him out in his new Quentin Tarantino-produced action flick out December, The Man with the Iron Fists:
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