Paramparā of the Atharva Veda and Purāṇas; Definition of a Purāṇa
Daśa-lakṣaṇam
सर्गोऽस्याथ विसर्गश्च वृत्तिरक्षान्तराणि च । वंशो वंशानुचरितं संस्था हेतुरपाश्रय: ॥ ९ ॥ दशभिर्लक्षणैर्युक्तं पुराणं तद्विदो विदु: । केचित् पञ्चविधं ब्रह्मन् महदल्पव्यवस्थया ॥ १० ॥
sargo ’syātha visargaś ca vṛtti-rakṣāntarāṇi ca vaṁśo vaṁśānucaritaṁ saṁsthā hetur apāśrayaḥ
婆罗门啊,通晓者说:具十种标相者名为《往世书》。亦有人依“大与小”的分类而说:大往世书说十种,小往世书说五种。
The ten subjects of a great Purāṇa are also described in the Second Canto of Śrīmad-Bhāgavatam (2.10.1) :
It lists core Purāṇic subjects such as creation (sarga, visarga), cosmic maintenance, manvantaras, dynasties and their histories, dissolution, the ultimate cause, and the supreme shelter (apāśraya), understood as Bhagavān.
He was clarifying how the Bhāgavatam is structured and what a true Purāṇa contains, so Parīkṣit could grasp the scripture’s scope while preparing for death through hearing Hari-kathā.
Take refuge in the Lord through hearing, chanting, and remembering Him; let spiritual shelter guide priorities, reduce fear, and give meaning beyond temporary worldly changes.