Shatapatha Brahmana 7.1.1.29

7.1.1.29

sakthyāvasyaite | te nānopadadhāti nānā sādayati nānā sūdadohasādhivadati nānā hīme sakthyau dve bhavato dve hīme sakthyau paścādupadadhāti paścāddhīme sakthyāvagrābhyāṃ saṃspṛṣṭe bhavata evaṃ hīme sakthyāvagrābhyāṃ saṃspṛṣṭe

These two are his (Agni's) thighs,--separately he puts them on, separately he 'settles' them, separately he pronounces the Sûdadohas verse upon them, for separate are these two thighs. There are two of them, for there are two thighs. Behind he puts them on, for behind are those thighs. At their upper ends they are joined (to the central ones), for so are these thighs joined (to the body) at their upper ends.