The fact that Christ was the last sacrifice and Temples are no longer needed or required (according to Paul, the New Covenant “temple” is your body) except in Mormonism, where their Temple ritual is a requirement to enter the highest Heaven and become a god, fulfills the following prophecy:
2 That ye be not soon shaken in mind, or be troubled, neither by spirit, nor by word, nor by letter as from us, as that the day of Christ is at hand.
3 Let no man deceive you by any means: for that day shall not come, except there come a falling away first, and that MAN OF SIN be revealed, the son of perdition;
4 Who opposeth and EXALTETH HIMSELF ABOVE ALL THAT IS CALLED GOD [you will pass by all angels and become a god], or that is worshipped; SO THAT HE AS GOD SITTETH IN THE TEMPLE OF GOD [the false spirit inside our bodies], shewing himself that he is God. (2 Thessalonians 2)
Q. Were Joseph Smith, Brigham Young, and every Church leader who influenced temple doctrine swayed by the Man of Sin/Son of Perdition spirit?
A. Yes.