What is the connection between this Parshah and the previous one?
Rashi and Targum Yonasan (in Pasuk 15): Someone who withholds the Matnos Kehunah from the Kohen, will ultimately need to bring him his wife as a Sotah. 1
See K'li Yakar.
Why does the Torah repeat the word "Ish"?
Rashi: Because the woman sinned against two 'men'
Because, as the Gemara says in Sotah, 17a, the Shechinah dwells between and a man and woman who are meritorious.
What are the implications of the term "Sotah"?
Rashi #1 (citing Tanchuma): It is equivalent to "Shotah" (with a 'Shin'), because a people do not commit adultery unless a spirit of idiocy enters into them. 1
And what are the connotations of "u'Ma'alah bo Ma'al ba'Hashem"?
Rashi: Refer to Vayikra, 5:15:1:1.
Ramban, Targum Onkelos and Targum Yonasan: Refer to Vayikra, 5:15:1:2.
Seforno: 'She desecrated the holiness of Hashem that He loves with regard to the sanctity of marriage, by hugging and kissing, and the like, another man'. 1