What is the ruling on sitting between the two prostrations with the toes erect and the buttocks placed on the heels, and was this sitting prohibited?

Scholars have differed in their interpretation of the prohibited iq'a' (sitting on one's haunches). Some said it is to raise the feet and sit on the heels. Others said it is to sit on the buttocks and raise the knees, like the iq'a' of a dog or a wild animal, and this latter form is the one that is prohibited. As for sitting on the heels, it is permissible; in fact, it is from the Sunnah (definition).

Many hadiths have been narrated prohibiting iq'a', but none of them are authentic. It is authentically reported from Ibn Abbas and Ibn Omar that sitting on the feet (placing the tips of the toes on the ground, placing the buttocks on the heels, and placing the knees on the ground) is Sunnah, and this is what some Companions did.