Answer
That is actually against the GBC’s own resolution. Their resolution clearly states that on the altar there should be only Śrīla Prabhupāda, and at most, one’s own guru’s picture may be kept temporarily during pūjā. After the pūjā is finished, that picture should be removed. This is a written guideline.
Why was this rule made? Because if such practices are freely allowed, then how many pictures will eventually accumulate on ISKCON altars? That is one concern.
Secondly, there is already a history behind this. In the past, when certain individuals were placed on the altar alongside Śrīla Prabhupāda and the great paramparā, some of them later fell down in very serious ways. This created an extremely embarrassing situation for the GBC—imagine someone being worshipped on the altar, and later it is discovered that they were involved in activities like intoxication or illicit behavior. To prevent such situations, these restrictions were introduced.
But the approach often seems reactive—like allopathy. When a symptom appears, a quick rule or resolution is imposed, rather than addressing the root issue, as Ayurveda aims to do. Similarly, when problems arise, immediate resolutions are passed to control the situation, such as allowing a guru’s picture only temporarily during pūjā.
Still, one may question: if someone is truly a guru, then why not establish them permanently? And if not, then why treat them as such even temporarily? This inconsistency raises questions.
Practically also, how much can be controlled? For example, in some temples like Bhubaneswar, the deity of Gaur Govinda Maharaj has been installed on the altar. Once such a precedent is set, what prevents future generations from adding more gurus? Over time, the altar could become overcrowded with multiple guru deities.
Even Śrīla A. C. Bhaktivedanta Swami Prabhupada himself gave a clear standard: his own spiritual master, Bhaktisiddhanta Sarasvati Thakur, should have a deity on the altar, while others in the paramparā can be represented through pictures. His instruction was that in all ISKCON temples, his Guru Mahārāja’s deity should be present.
This is his movement—he is the Founder-Ācārya. Others have not founded this movement, so the question arises whether it is appropriate for multiple individuals to be established on the altar in the same way.
