He had an accident while jogging, resulting in scratches and the eyepatch. The caption of the picture, which was posted on Twitter, literally said "Am curious/excited for the memes". His PR knows how to catch the attention of the internet lol
He says it's jogging, but that's just to hide his secret identity as masked super hero at night where he runs through the streets of Berlin and fights evildoers with his fists.
the caption was way more than that, it started with a quote of the beginning of a popular German proverb on Schadenfreude:
"Wer den Schaden hat..." - "Who has the damage..."
The latter part of the proverb exists in two versions, the more benign one ends in "...braucht für den Spott nicht zu sorgen" - "...doesn't have to ask for ridicule", the more cynical version ends in "...spottet jeder Beschreibung" - "...is ridiculous beyond description". Adding appropriate ending was left to the reader.
To be honest, I was surprised of seeing such a sense of humour in Scholz and his PR team, the jogging accident must have scraped off some of the Teflon he is usually coated with.