Is it saying that even in a cold stone, if someone continues to sit on top of it, he or she could warm the stone in three years. It values a sprit of patience.
"・・・暖まるように、" = "・・・暖まる。この例が示すように、"
---I added more-----------------------------------------------------------------
石の上にも三年とは、冷たい石でも三年間座り続ければ暖まるように、何事にも忍耐強さが大切だという意味です。
石の上にも三年とは、何事にも忍耐強さが大切だという意味です。
"Perseverance preails: Staying on the stone for three years" means "Patience is important at everything."
冷たい石でも三年間座り続ければ暖まるように、何事にも忍耐強さが大切だ。
If someone continues to sit on top of it, he or she could warm the stone in three years. (This is the meaning of "石の上にも三年")
As this Perseverance preails shows, Patience is important at everything.
冷たい石でも三年間座り続ければ暖まる(と言います。この例が示すように)、何事にも忍耐強さが大切だ。