Sa'id bin Jubayr narrates from Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) concerning a man who gave his wife a thousand divorces. He said: Three divorces have made your wife unlawful for you, and the rest are a sin upon you, for you have made a mockery of the verses of Allah. So this hadith indicates the sin of giving more than three divorces.
(b) Ata' narrates from Ibn Abbas (may Allah be pleased with them both) concerning 100 divorces: With 97 you have made a mockery of the verses of Allah.
Imam al-Shafi'i (may Allah have mercy on him) says: Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) found fault with giving more than three divorces.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الخلع والطلاق / 14945