Its a famous saying, but its slightly different from what the original saying is. The original saying is
堪忍の成る堪忍は誰もする成らぬ堪忍するが堪忍
Tolerating that which can be tolerated is something anyone can do
Tolerating that which is truly intolerable, is true tolerance
In English we might just say "patience is a virtue", but that somehow misses the mark of the Japanese original, which asks the reader to dig deep in terms of acceptance, endurance, and tolerance.
Yours seems to read
堪忍ハなる堪忍か かんにんが 成らぬ堪忍するが堪忍
Which feels like its slightly mangled the grammar of the original, but it could be some classic syntax that is lost on me.
Next to that is 七十九年 親和出 (79 year, by Shinna), and then the seal of Mitsui Shinna.