It is narrated from Hazrat Mughira bin Hakim that he saw Sayyiduna Abdullah bin Umar (may Allah be pleased with them) sitting between the two prostrations on the toes of both feet, and then he would go into prostration. When he finished the prayer, this was mentioned, so Sayyiduna Abdullah (may Allah be pleased with him) said that sitting like this in prayer is not correct, but I sit like this due to illness.