Question
Who is devi in devi suktam?
Answer
Vaak Suktam Or Devi Suktam is in Rig- Veda - Mandala 10 as sukta 125.
The Rishika of this sukam is Vagambharni i.e. this sukta has been heard by a female sage by name Vaak , who is the daughter of Rishi Ambhrina and so the sukta is also called as the VakAmbharni Sukta.
The explanation given in various sources say that this suktam came out from deep of her heart when she was in communication with Brahman in her worship in exalted state. Here the Rishika is identifying herself with Devi and hence the Devata of this sukta is also VakAmbharni .She has eulogized herself in this sukta as Brahman , here resemblance to Advaita Philosophy.
According to some scholors this sukta is for power of speech and is not related with goddess . But from another point of view this sukta is gateway to Saptasati Chandi.
But we can see the pointing in some mantras towards Devi Laxmi - I am the bestowe of wealth and I grant the wealth and I reside in the oceans. etc. - Mantra 2 & 7
अहं सोममाहनसं बिभर्म्यहं त्वष्टारमुत पूषणं भगम |
अहं दधामि द्रविणं हविष्मते सुप्राव्ये यजमानाय सुन्वते || 2 ||ahaṃ somamāhanasaṃ bibharmyahaṃ tvaṣṭāramutapūṣaṇaṃ bhagham |
ahaṃ dadhāmi draviṇaṃ haviṣmatesuprāvye yajamānāya sunvate ||अहं सुवे पितरमस्य मूर्धन मम योनिरप्स्वन्तः समुद्रे |
ततो वि तिष्ठे भुवनानु विश्वोतामूं दयांवर्ष्मणोप सप्र्शामि || 7||ahaṃ suve pitaramasya mūrdhan mama yonirapsvantaḥ samudre |
tato vi tiṣṭhe bhuvanānu viśvotāmūṃ dyāṃvarṣmaṇopa spṛśāmi ||
As Laxami is often described as emerging from depth of ocean during churning and is the goddess of wealth , prosparity in later Vedic scriptures like puranas.
At the same time we can also observe the presence of of Goddess Saraswati in some - mantras as - I bless the humans to become Poet , scholor , intelligent i.e. fluent or persuasive in speaking or writing. -Mantra 5
अहमेव स्वयमिदं वदामि जुष्टं देवेभिरुत मानुषेभिः |
यं कामये तं-तमुग्रं कृणोमि तं ब्रह्माणं तमृषिं तं सुमेधाम || 5 ||ahameva svayamidaṃ vadāmi juṣṭaṃ devebhirutamānuṣebhiḥ |
yaṃ kāmaye taṃ-tamughraṃ kṛṇomi tambrahmāṇaṃ taṃ ṛṣiṃ taṃ sumedhām ||
And in some she is said to be fighting for humans i.e. as the Devi Durga told in puranas. - Mantra 6.
अहं रुद्राय धनुरा तनोमि ब्रह्मद्विषे शरवे हन्तवा उ |
अहं जनाय समदं कृणोम्यहं द्यावापृथिवी आ विवेश || 6 ||ahaṃ rudrāya dhanurā tanomi brahmadviṣe śarave hantavāu |
ahaṃ janāya samadaṃ kṛṇomyahaṃ dyāvāpṛthivī āviveśa ||
So it's clear that this Sukta is definitely related to Goddess. As we can see from above.
Here Devi is proclaming herself as source of all the creation , source of all creative power , conciousness i.e. Brahman herself.
Conclusion - So the devotees can say that the Goddess mentioned in this suktam is Adi-Parashakti with all her aspects and forms like Durga , Laxmi , Saraswati etc. As Adi Parashakti is the supreme Brahman in Shakta tradition. And as she is described as Brahman in the sukta , She is Adi-Parashakti. This sukta is chanted during the worship of the Universal Goddess in any form.
Here is complete Devi Suktam with translation and some good explanation.
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