The primary rule of construction of a document is the intention of the executants, which must be found in the words used in the document. The question is not what may be supposed to have been intended, but what has been said. We need to carry on the exercise of construction or interpretation of the document only if the document is ambiguous, or its meaning is uncertain. If the language used in the document is unambiguous and the meaning is clear, evidently, that is what is meant by the executants of the document. Contemporary events and circumstances surrounding the execution of the document are not relevant in such situations.
Lord Hale in King v. Meling (1 Vent. At p. 231), in construing a testamentary disposition as well as a settlement, pointed out that the prime governing principle is the “law of instrument” i.e. the intention of the testator is “the law of the instrument”. Lord Wilmot, C.J. in Doe Long v. Laming (2 Burr. At pp. 11-12) described the intention of the testator as the “pole star” and is also described as the “nectar of the instrument. In Re Stone, Baker v. Stone [(1895) 2 Ch. 196 at p. 200] the Master of the Rolls said as follows: “When I see an intention clearly expressed in a Will, and find no rule of law opposed to giving effect to it, I disregard previous cases.” Coleridge, J. in Shore v. Wilson [9 Cl. & F. 355, at p. 525] held as follows:
“The intention to be sought is the intention which is expressed in the instrument, not the intention which the maker of the instrument may have had in his mind. It is unquestionable that the object of all expositions of written instruments must be to ascertain the expressed meaning or intention of the writer; the expressed meaning being equivalent to the intention … It is not allowable …. To adduce any evidence however strong, to prove an unexpressed intention, varying from that which the words used import. This may be open, no doubt, to the remark that although we profess to be explaining the intention of the writer, we may be led in many cases to decide contrary to what can scarcely be doubted to have been the intention, rejecting evidence which may be more satisfactory in the particular instance to prove it. The answer is, that the interpreters have to deal with the written expression of the writer’s intention, and courts of law to carry into effect what he has written, not what it may be surmised, on however probable grounds, that he intended only to have written.”
In Halsbury’s Laws of England, 4th Edn., Vol.50, p.239, it is stated:
“408. Leading principle of construction.- The only principle of construction which is applicable without qualification to all wills and overrides every other rule of construction, is that the testator’s intention is collected from a consideration of the whole will taken in connection with any evidence properly admissible, and the meaning of the will and of every part of it is determined according to that intention.”
Underhill and Strahan in Interpretation of Wills and Settlements (1900 Edn.), while construing a will held that “the intention to be sought is the intention which is expressed in the instrument not the intention which the maker of the instrument may have had in his mind. It is unquestionable that the object of all expositions of written instruments must be to ascertain the expressed meaning or intention of the writer; the expressed meaning being equivalent to the intention……….”
Theobald on Wills (17th Edn. 2010) examined at length the characteristics of testamentary instruments. Chapter 15 of that book deals with the General Principles of Construction. Referring to Lindley L.J. in Musther, Re (1889) 43 Ch.D. 569 at p.572, the author stated that the first rule of will construction is that every will is different and that prior cases are of little assistance. Referring to Sammut v. Manzxi  1 W.T.L.R. 1834, the author notices that the Privy Council had approved the approach of considering wording of the will first without initial reference to authority, and commented that “little assistance in construing a will is likely to be gained by consideration of how other judges have interpreted similar wording in other cases.
Supreme Court in A. Sreenivasa Pai and Anr. v. Saraswathi Ammal alias G. Kamala Bai (1985) 4 SCC 85 held that in construing a document, whether in English or in any Indian language, the fundamental rule to be adopted is to ascertain the intention adopted from the words employed in it. Reference may also be made to the judgment of the Privy Council in Rajendra Prasad Bose and Anr. v. Gopal Prasad Sen AIR 1930 PC 242 and C. Cheriathan v. P. Narayanan Embranthiri and Ors. (2009) 2 SCC 673.