History. India has always had an amicable relationship with both Israel and Palestine. This is possible because leaders on all sides are aware of each others local and international political constraints.
Even if it was one of the last non-muslim state to recognize the Israeli state, it had allowed Israel to open a consulate in India in 1953 itself and maintained an open channel between the two countries. Israel has also helped India by supplying it arms during wars in 1962, 1965, 1971 and later in 1999, and also sharing intelligence on Pakistan and some terrorist groups. At the same time India was the first non-Arab country to recognize the PLO, and later allowed it to open an embassy with full diplomatic privilege in India. A NAM summit held in India issued a strong statement of solidarity for Palestine because of India's diplomacy. India also supported the Palestinian uprising in Gaza and West Bank, while condemning Israel's "iron fist" policies that lead to it. The Palestinian President, Arafat, in turn, was one of the few muslim leaders who supported India's stand on Kashmir, against Pakistan.
But, due to its colonial history and politics bound in Gandhian philosophy, India has always condemned the use of violence as a political tool. This has always been a point of contention for India with both the Israelis and Palestinians. This aspect is what has slightly changed, temporarily, in the Indo-Israel relationship - India may today seem to be more forgiving towards Israel's use of violence, than in the past.
This is because the polity of both India and Israel are today dominated by the right, for whom violence is part and parcel of their political ideology.
Both countries today have authoritarian leaders with scant respect for democracy, and a shared ideology of establishing a state with a religious identity. Both leaders also have a fundamentalist political inclination to deny the rights of the minorities in their state and treat them like second-class citizens. This personal rapport between Israeli PM Netanyahu and Indian PM Modi is why there is, currently, a more visible "pro-Israel" tilt in India's foreign policy.
Media articles (including the ones I have cited) that suggest that India's relationship has suddenly "accelerated" to strategic partnership due to the excellent chemistry between Netanyahu and Modi, are erroneous and partly propaganda. The reality is that it's just a natural evolution of their past foreign policies, and changing international order. This is apparent when you learn that even in the 80's, Israel and India once considered a joint military operation to sabotage Pakistan's nuclear program.
The only difference is that previous Israeli and Indian government were more prudent about not publicising the strategic nature of their relationship, while the current leaders today prefer to carelessly use it for PR for domestic political gains. (Hence all the increased media spotlight on the relationship).
Note though that keeping in line with its non-alignment foreign policy, India has always ensured its relationship with Israel was never at the cost of its commitment to the Palestinian people and vice-versa.
The "strong friendship" between Netanyahu and Modi didn't prevent India from still voting in favour of the UN resolution that condemns Israeli settlement activities in ‘Occupied Palestinian Territory’. Nor has Modi's government designated or banned Hamas as a terrorist organisation. (A Hamas leader even publicly - virtually - addressed a pro-Palestine gathering in Kerala, India, highlighting the support the Palestinian cause has among many Indians.)
Consistent with its political stand on Palestine, India recently (December 2024) voted against Israel, in favour of a recent UN resolution which called for Israel to withdraw from Palestinian territories occupied since 1967, including East Jerusalem.
References:
- How India-Israel ties progressed
- India’s Hindutva Proponents and Zionist Israel: Strange Bedfellows
- When Pakistan feared Israel, India would attack its nuclear weapon sites
- Arafat for Kashmir solution within Shimla pact
- Arafat didn't support Kashmiris: Geelani
- Hamas leader's virtual address in Malappuram: Police begins inquiry
- India wants Israel to exit Palestinian land, votes for UN resolution