"The New Testament account of the crucifixion of Christ would seem to indicate that the Savior was crucified the very week he became thirty-three years of age. The Book of Mormon not only substantiates this account, but also provides us with an exact date of the crucifixion. According to the Nephite calendar system, the Savior was crucified 'in the thirty and fourth year, in the first month, on the fourth day of the month.' (3 Nephi 8:5.) Although we are not certain when the first month of the Nephite calendar would occur, if the Nephites were using the same calendar system as the Hebrews, the first month would be in the spring of the year sometime between about the middle of March and the middle of April." (Daniel Ludlow, A Companion To Your Study of the Book of Mormon, p. 258-9)
Orson Pratt
"We find that the ancient Israelites on this continent had a sign given of the exact time of the crucifixion and a revelation of the exact time of the Savior's birth, and according to their reckoning, they made him thirty-three years and a little over three days old from the time of his birth to the time that he hung upon the cross." (Journal of Discourses, 13:127)
Orson Pratt
"It is generally believed and conceded by the learned, who have investigated the matter, that Christ was born in April. I have seen several accounts--some of them published in our periodicals--of learned men in different nations, in which it is stated that, according to the best of their judgment from the researches they have made, Christ was crucified on the 6th of April. That is, the day on which this church was organized." (Journal of Discourses, 15:257)