sheet anchor

1691, Ezekiel Hopkins, An Exposition of the Ten Commandments, with Other Sermons, London: Nathanael Ranew, “The Ninth Commandment,” p. 62, And doubtless when other Arguments have been baffled by a Temptation, this hath been a Sheet Anchor to the Soul, and hath often held it in the greatest Storms, when the Wind and Waves have beat most furiously against it.

1971, Nelson Mandela, letter to the wife of fellow-prisoner Mac Maharaj dated 1 February, 1971, in Sahm Venter (ed.), The Prison Letters of Nelson Mandela, New York: Liveright, 2018, It is the prettiest portrait of her that I’ve seen. Its message is clear & unambiguous: Darling I’m the centre of the universe; sheet anchor of all your dreams!