Library E. W. Bullinger Number in Scripture
Part II — Spiritual Significance
Twenty-five
being the square of five (52 or 5x5), expresses the essence of the signification of five, i.e. grace, whether used alone or occurring as a factor in larger numbers.
E. W. Bullinger, Number in Scripture: Its Supernatural Design and Spiritual Significance, fourth edition revised (London: Eyre & Spottiswoode, 1921). Public domain. Sectioned HTML transcription via Levend Water; bibliographic record and page scan of the 1894 edition from the Claremont School of Theology collection via Internet Archive.