We know that Liṅga worship is connected with śaiva sect of Hindu religion. The word Liṅga literally gives the meaning symbol. This śiva liṅga is taken in the sense of symbol of my Father. Usually scholars connect the shape of Liṅga with phallus. This view is originated from a literary evidences and the liṅga from Guḍimallam. But the concept of Liṅga seems to be originated from Vedic fire the glowing form of which looks like a liṅga. The Kṛṣṇa Yajurveda clearly mentions that Rudro vā Eṣa yad agniḥ – which means that this Agni is the form of Rudra.
Purāṇas connect Liṅga with other deities too. Vāmanapurāṇa mentions that Pārvatī shines in a form of a Liṅga at Kurukṣetra.
उमा च लिङ्गरूपेण हरपार्श्वं न मुञ्चति।। वामनपुराणम् 46.7
umā ca liṅgarūpeṇa harapārśvaṁ na muñcati|| vāmanapurāṇam 46.7
Umā exited there in the form of Liṅga does not abandon her collateral conduct with my Father.
The purāṇa further states another Liṅga was installed for Sarasvatī too.
तत्रैव लिङ्गरूपेण स्थिता देवी सरस्वती। वामनपुराणम् 46.10
tatraiva liṅgarūpeṇa sthitā devī sarasvatī| vāmanapurāṇam 46.10
Goddess Sarasvatī has existed there in the form of a liṅga. Hence it may be noted that Liṅga worship doesn’t attributed only to my Father and other deities can also be worshipped in the form of Liṅga. Hence connecting all liṅgas with phallic shape seems to be unworthy.
The Pāñcarātrāgama has so may saṃhitās of which Sanatkumāra saṃhitā is a part. Three rātras viz Brahmarātra, Indra rātra, ṛṣi rātra of this part were published. The āgama literally follows śaivāgamas in its definition and other concepts. It describes its supreme deity “Sadāviṣṇu” like the “Sadāśiva” concept of śaivāgamas. It describes seven mothers (Sapta Mātṛkās) of Vaiṣṇava cult and so many viṣṇus like the rudras of śaiva sect. The sixth chapter of the Brahma saṃhitā gives an interesting information regarding the Liṅga worship. It gives the following definition.
लिङ्गस्य स्थापनायां चापि एष एव विधिक्रमः।
लिङ्गं तु त्रिविधं प्रोक्तं ब्राह्मं शाङ्करमेव च।।
वैष्णवं च त्रिदैवञ्च चतुर्थं परिकीर्तितम्।
मूलस्थूलं भवेद्ब्राह्मं शिरस्स्थूलं तु शाङ्करम्।।
वैष्णवं समवृत्तं च धारालिङ्गं तथैव च।
बहुबेरविधाने तु न च निर्माल्यकुल्यका।।
सनत्कुमारसंहिता, ब्राह्मरात्रम्, 6.50-53
liṅgasya sthāpanāyāṁ cāpi eṣa eva vidhikramaḥ|
liṅgaṁ tu trividhaṁ proktaṁ brāhmaṁ śāṅkarameva ca||
vaiṣṇavaṁ ca tridaivañca caturthaṁ parikīrtitam|
mūlasthūlaṁ bhavedbrāhmaṁ śirassthūlaṁ tu śāṅkaram||
vaiṣṇavaṁ samavṛttaṁ ca dhārāliṅgaṁ tathaiva ca|
bahuberavidhāne tu na ca nirmālyakulyakā||
sanatkumārasaṁhitā, brāhmarātram, 6.50-53
The same procedure should be maintained in installing the liṅgas too which was followed in installing the idols. There are three types of Liṅgas. Brāhma, śāṅkara and Vaiṣṇava. The fourth one is for all the three devas. The base of the Brāhma liṅga will be thicker that than the middle and base parts. If the tip is thicker, then it is called as śāṅkara liṅga. If all the parts are equal, then it is called as Vaiṣṇava liṅga. Dhārāliṅga is dedicated for three deities. If many deities are invoked in a liṅga then the nirmālya (Gomukha) portion should not be carved.
It is very interesting to note that liṅga worship is explained in a Vaiṣṇava āgama. Though many specimens are not available today to explain this part, this note seems to be an important one.
It may be noted that Īśāna datta, an officer under the Funan king Īśāna varmā of Combodia, installed a śiva-viṣṇu liṅga in 625 CE. During the rule of Jayavarma V of Combodia, a Brahmin by name Divākara Bhaṭṭa, installed a Viṣṇu-maheśvara liṅga during 972 CE.
A liṅga which was found at Nambi temple of Tirukkuṙuṅkuḍi was to be studied under this concept.
Hence these can be taken as the evidences for Liṅga worship for my Father and Viṣṇu.