The Rebbes opinion regarding moving to, and visiting, Eretz Yisrael:
In a public talk in the year 1955, the Rebbe discouraged the campaign of encouraging every Jew from leaving the Diaspora for the sake of fulfilling the Mitzvah of dwelling in Eretz Yisrael due to several factors. One of the mitigating factors for the negation is the fact that the Poskim rule that one must be more careful in his religious observance when he lives in Eretz Yisrael, and if he will not be more careful, then he is not to travel to Eretz Yisrael.
The requirement for a “spiritual visa”: Accordingly, the Rebbe stated on a number of occasions that one must have a spiritual visa from G-d to be allowed to visit Eretz Yisrael, which means that he is of proper spiritual stature and observance to be allowed entry into G-d’s personal palace.
The need to add in Torah observance while there: The Rebbe thus directed individuals who planned to visit Eretz Yisrael that they should add in their observance of Torah and Mitzvos while they are there, and that this addition should be done daily during their stay.
Greater evil inclination: The Rebbe stated that dwelling in Eretz Yisrael is a great responsibility. The Rebbe stated that in Eretz Yisrael there is a much stronger evil inclination which challenge people in their religious observance, and it is unclear if the people who successively overcome their inclination in the diaspora will be successful in doing so also in Eretz Yisrael.
Sins are more severe: The Rebbe stated that a sin in Eretz Yisrael is considered a lot more severe by G-d than that same sin that is transgressed in the diaspora.
Visiting for tourism purposes: The Rebbe discouraged people from traveling to Eretz Yisrael simply for the sake of tourism and as a tourist attraction, being that it is the palace of the king, and therefore one should only visit if doing so will add in one’s holiness and fear of heaven.
Better use the money for charity: In one letter, the Rebbe discouraged an individual from visiting Eretz Yisrael due to the lack of foreseen benefit of such travels, and due to that since he plans on staying in Eretz Yisrael for several months, it enters him into the unnecessary question of whether he is now allowed to leave Eretz Yisrael. The Rebbe stated to the individual that since there is no foreseen benefit in his travels, it is better to use the money which he allocated for the travels for purposes of charity. Certainly, he should not enter himself into financial distress in order to make the travels.
Not to stay for more than 30 days: The Rebbe directed individuals visiting Eretz Yisrael to not remain there for thirty consecutive days, due to it entering him into the unnecessary question of whether he is now allowed to leave Eretz Yisrael. This will be further discussed in D.
 See Shulchan Menachem Vol. 7 pp. 138-150; Shaareiy Eretz Yisrael [Heichal Menachem] p. 247 and onwards; Likkutei Sichos Vol. 2 p. 619; 12 p. 257; Toras Menachem 15:111; 16:353; Igros Kodesh 13:193; 15:452; 16:353; 18:404; 19:49; 26:444
 Printed in Likkutei Sichos Vol. 2 p. 619
 Rebbe Chaim in Tosafus Kesubos 110b; Tashbeitz Katan 559; See Igros Moshe E.H. 3:102
 See Likkutei Sichos ibid and Vol. 12 p. 257
 See Likkutei Sichos Vol. 12 p. 257; Toras Menachem 15:111; Igros Kodesh 13:193; 19:49; 26:444
 Igros Kodesh 15:452; 19:49; 26:444
 Likkutei Sichos Vol. 12 p. 257
 Toras Menachem 16:353
 Heichal Menachem 3:270
 Igros Kodesh 18:404