The ruling on tayammum (dry ablution with clean earth) in the presence of water due to fear of exposing the 'awrah (part of the body that must be covered)

Question:
May Allah reward you. Honorable Shaykh, this questioner says: If we are on the shore of the sea, is it permissible to perform tayammum (dry ablution with clean earth) while water is available, out of fear of exposing the 'awrah (the part of the body that must be covered)?

Answer:
Regarding the relationship between uncovering and wudu' (the ablution for prayer): there is no uncovering in wudu'; they perform wudu' and pray. As for istinja' (cleaning oneself after relieving oneself), istijmar (cleaning with a stone) takes its place; they perform istijmar that cleanses, and it suffices in place of istinja' with water if the intention is to seek ease. There is no uncovering in wudu'. If a person is in a state of janabah (major ritual impurity) and needs to perform ghusl (the full ritual bath), he should cover himself, stand behind a tree, and place a garment so that he can perform ghusl behind it. He should find a secluded spot and take water with him; he does not perform ghusl in the sea. He takes water with him and goes to a secluded place, or moves away from people and performs ghusl. As for performing tayammum while water is available, it is not permissible. This does not expose the Messenger (peace and blessings be upon him). He should go and move away from people, or cover himself with a tree, a garment, or a camel. Yes.