Body has a beginning as well as an end
1. Beginningless infinite
2. Beginningless with an end
3. With beginning and infinite
4. With beginning and an end
In the first category come those substances, which have neither beginning nor an end e.g. soul, dharma, adharma etc.
In the second category comes karma, which is attached with the soul since beginningless time; but can be separated through partial annihilation nirjara.
Omniscience, moksha etc. are covered in the third category, which though have a beginning but no end. Once one gets omniscience, it always remains. He becomes omniscient for all times to come. He is never without omniscience or without all-knowledge. Same thing can be said about moksha also. Once acquired, it is never lost; therefore, it has a beginning and is infinite.
In the fourth category comes the body. It is born, grows, becomes old and dies i.e. after being separated from the soul it is burnt here only; hence, it has a beginning and an end.
- Prasnavyakarana 1/2
Since body has a beginning as well as an end, omniscient have said to not to get ourselves involved in the futile body and sense pleasures rather should practice self denial. We should aim and work in the direction of achieving the eternal peace and happiness(Moksha).