Chasidut for Pesachim 237:15

Another aspect of why the Torah tells us that Yitzchok chose ‎to stroll in the field, is provided by the additional detail of the ‎time of day when this occurred, i.e. shortly before sunset, i.e. ‎לפנות ערב‎. Our sages (Pessachim 119) give some examples of how ‎G’d’s viewing matters differs from the way His creatures, human ‎beings, view the same matters. Example: When one of G’d’s ‎creatures suffers a defeat, he reacts by being saddened and ‎becoming depressed. G’d, on the other hand, is overjoyed when ‎one of His creatures prevails in a discussion with Him. When G’d ‎had originally suggested that Moses become a substitute for the ‎Jewish people whom He intended to destroy after the episode ‎with the golden calf, and Moses pointed out to him that this ‎would not be a good idea, as the chances of a new Jewish people ‎with only one founding father, himself, being better than the ‎previous Jewish people who had three founding fathers were very ‎slim, G’d was overjoyed to accept Moses’ argument as superior to ‎His own. (Compare psalms 4,1 where David alludes to this) The ‎Midrash (Tanchuma Ki Tavo 1) takes this thought even further by ‎generalizing that ”G’d issues decrees and the righteous on earth ‎cancel these decrees.”‎
When G’d was guiding His universe before having created ‎man, He did so all by Himself. He did not need to take into ‎consideration how His creatures would view His actions, i.e. His ‎will reigned supreme. Once He had created free willed human ‎beings, He had to seriously consider how the righteous among ‎them would view His actions. Our sages allude to this when they ‎said: (Bereshit Rabbah 19,7 ‎עקר שכינה בתחתונים‎, (loosely translated) ‎‎“G’d’s presence is occupied primarily with His creatures in the ‎‎‘lower’ part of the universe,” [i.e. He has to justify Himself to the ‎righteous people on earth. Ed.]
This principle of G’d’s involvement in man’s pursuits not ‎merely being restricted to viewing it from the celestial regions, is ‎documented in Exodus 19,20 ‎וירד ה' על הר סיני‎, “Hashem ‎descended on Mount Sinai., etc.” What was the reason that G’d ‎saw fit to leave the lofty spheres of heaven? He prepared to act in ‎accordance with what the ‎צדיקים‎, the righteous expected from ‎Him. Being able to set the minds of His righteous at rest is the ‎greatest satisfaction that G’d, their Creator, can experience.
In our portion, this is alluded to when the Torah describes ‎Yitzchok as meditating in “the field,” or, [in the words of our ‎sages ] “Avraham viewed G’d as ‘a mountain;’ Yitzchok viewed ‎Him as a ‘field,’ whereas Yaakov viewed Him as a ‘house;’ this is ‎why he promised to build a “house for Him.” The tzaddikim ‎learned to become progressively more familiar with G’d. [The ‎anecdotes about our author that are appended to his ‎commentary on the Torah, reflect the fact that the author was no ‎exception to this rule. Ed.] Being able to feel close to G’d, i.e. on ‎the field, enabled Yitzchok, whose very name symbolized joy, ‎laughter, to become more intimate with his Creator. The word ‎שדה‎ is also known as ‎חקל‎, “(as in ‎חקלאות‎ the pursuit of ‎agriculture.) [The author describes the righteous as being ‎described as ‎שדה חקל‎, but I have not been able to find the source ‎for this. ‎‎‎