Worship of Hari Hara forms started late
It is claimed that Lord could be an image of Harihara. In this regard we should consider as to when did Harihara forms came into vogue?
As a matter of fact, Hari Hara forms of worship i.e. fused forms of Siva and Vishnu, was quite late and it originated out of the attempts at syncretization, and bringing together of Vaishnavas and Shaivas with the primary intention of fighting against the enemies of Brahmanism, and their appearance starts around eighth or ninth century, in any case much later than the appearance of the murthi of Lord of Tirumalai. So in the present context, when the time of appearance of image of Tirupati is thought to be earlier, it is irrelevant and should not have been necessary to consider the Lord as a Hari Hara manifestation. But as the modern scholarship is keen on declaring it as a Hari Hara murthi, we will consider this view in short.
Contradictory remarks of Sitapati
Sitapati gives the following account to show it to be a Hari Hara murthi:
"Several Puranas no doubt say that Venkatachalam is a Vishnu Kshetram. The Svetha - Varaha Murthi and the Lord Venkatesvara are the deities of Tirumalai. The acceptance of the Lord as a 'Hari-Hara Murthi' will in no way conflict with the claim of the Puranas that Venkatachalam is a Vishnu Kshetram. ..." [Sitapati:26]
Thus giving contradictory remarks, he gives the following points in support of this theory.:
1. "... The Lord's Hill also bears the name Srisailam, and Srisailam is sacred to Lord Siva."
2. "According to sri Dave, 'in the famous Dwadasa Jyotirlinga stotra of Sri Sankaracharya, there is a description of Mallikarjuna of the Srisaila mountain which is part of the Seshachlam Hills and Srisaila itself is used as a name for Tirupati."
3. "... puranas view the range of hill from Tirupati to Srisailam, famous for its Mallikarjuna temple as one unit."
4. Puranas give a graphic description of a cobra to hill associating four shrines viz. Kalahasti, Tirupati, Ahobilam, and Srisailam.
One could have laughed off these arguments, but for the personality like sri Sitapati, and his attempts to project his hypothesis in world Telugu Conference.
None of the above points is any evidence of it being a Hari Hara Murthi, as it only connects the shrine of Tirumalai with Srisailam. On the contrary, if anything, this Puranik link proves our point that all these were Buddhist shrines. The account of Srisailam is already narrated by us (chapter 7) showing it to be Buddhist shrine and how sword and fire was used to capture it for Brahmanism under the very supervision of Adi Shankara.
There is another hypothesis, which he has postulated is that of "Vyakta Vishnu and Vyakta-Avyakta Shiva", which seem to be more popular in recent times. This novel hypothesis contemplates that the Lord's image is not that type of Hari-Hara showing the fused forms of Vishnu and Shiva but because of certain features resembling both Shiva and Vishnu being present in the Murthi, it is still a Hari-Hara and that the 'early Alvaras' thought it to be "Manifested Vishnu, manifested-non-manifested Shiva". As the real evidence for this hypothesis as given by him, concerns Alwaras, we will discuss this point in the Chapters on Alwaras.