Ties between Moscow and the Arab Palestine go back to the very beginning.
The name "Palestine" came from Romans, to punish Jews, long before any Muslims existed. For the longest time, Muslims in the area just called themselves Muslims, Arabs, or Syrians.
Enter Moscow: Yassar Arafat was a Soviet created, funded, trained, figure. The Kremlin turned many Arabs into terrorists who fought for the "Palestinian" cause.
Mahmoud Abbas, current leader of the so-called Palestinians, is also a Russian agent. He studied at the Patrice Lumumba University in Moscow where his Russian handlers helped him write a PHD paper where he made the claim that the Holocaust was nothing more than a Zionist provocation.
Putin pledged military support to Palestinians. He is a critic of Israel's retaliatory strikes as "disproportionate" and "completely unacceptable." His government criticizes Israel's "illegal" actions while hosting Abbas in Moscow and increasing trade with Palestine.