Janine Gofar's indispensable C. S. Lewis Index: Rumours from the Sculptor's Shop (Riverside, CA: La Sierra University Press, 1995; ISBN 0-944450-19-9) lists (among others):
Mere Christianity Book II, Section 5, Paragraphs 3 and 7: Baptism as one of three things which spreads the Christ life in us
"Membership," The Weight of Glory, Paragraph 9: Baptism calls a Christian not into a collective but into a Body
Reflections on the Psalms, Chapter 5, Paragraph 10: "Our life as Christians begins by being baptised into a death"
[signed]
Paul F. Ford
(author of the Companion to Narnia and the Pocket Companion to Narnia )