The Full Form of RIP is Rest In Peace. RIP word is used by Christians because they don't burn the dead bodies but burry them. It is the phrase commonly written on the grave of the Catholics so that after death, their soul rest in peace. It is the Christians belief that God will do justice to them on the Day of Judgment, till then the body must be rest in peace. This strong faith is written in the Bible of the Christians.
In the 18th Century, the use of this phrase became very common on Christian Tombs. This term is mostly used in Christians religion and no other religion uses it.
There are various full form of rip used by different people in different situations.
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