Here is some more info from Wesley Huff on some specifics I didn’t get into in the video.
“I think at face value it looks less like an example of homoiteluton and more of an assimilation of Matt. 6:15. It's included in most later MSS from my look but from both internal and external considerations doesn't appear to be viable as going back as an original reading.
Its absence from Vaticanus and Sinaiticus is significant, the text of Mark in those two is as stable as you can get. Not to mention that Codex Washingtonianus has it missing and Codex W is pretty important in being a witness to multiple text type variations (it includes Alexandrian, Byznatine, and Western text-type examples). Mind you, Codex W's section between Mark 5-16 is a bit of a hodge-podge textually, but it still remains pretty reliable throughout nonetheless. The oldest Syriac manuscript, the fourth-century Sinaitic Palimpsest, does not contain the verse, nor do the Palestinian Syriac copies which all raises questions of authenticity in my eyes.”
Why is this verse missing from the ESV translation? Why does it have brackets in the NASB? Here's a summary of the reasons why this verse may not be original and how I think we should think about it. This is the shortest video in the whole Mark series so far and I'm just tossing it out there in the middle of a bunch of other content but I thought it was worth taking some time to discuss.
Here's the playlist to my three videos on manuscript issues and translations of the Bible (which I mentioned in the vid) https://www.youtube.com/watch?v=WclIZwBFhq0&list=PLZ3iRMLYFlHuzJhPtmrgqpVoXhjvqiIjW
Here's the entire Mark series playlist. I am absolutely LOVING this series and hope it blesses you tremendously. https://www.youtube.com/watch?v=7c7jWg60N_0&list=PLZ3iRMLYFlHuGenHwUdeiQ5M-uj5XW4sF
My website https://BibleThinker.org