The Coonan Cross Oath takes place on this date in 1653 as the Syrian Christian community rejects Portuguese authority, an important event in Kerala's history.

The Oath was taken at the Mattancherry Church by a large number of Syrian Christians led by Archdeacon Mar Thoma 1. The Oath was taken by the Nasranis, Syriac term for first Xtian converts in Asia, tying ropes to a cross. It was a protest against Portuguese attempts to enforce Latin rites of worship as against the traditional Syrian Christian rites. The mysterious disappearance of Syrian bishop Ahatallah who was believed to have been executed by Portuguese only fuelled the resentment further. The Oath led to a split in the Syrian Christian community with one group Pazhayakuttukar staying loyal to Catholic Church. While the other group, the Puthankuttukar led by Mar Thoma I followed the traditional Syrian Christian rites. This group branched out into Jacobite Syrian Xtian Church, Malankara Orthodox Xtian Church, while the Catholic supporting faction evolved into Syro-Malabar Church.