Sforno on Genesis 28:21/ספורנו על בראשית כ״ח:כ״א

1ושבתי בשלום, from all the problems besetting man, i.e. a reference to what the Talmud had called רוח רעה.

2והיה ה' לי לאלוקים, then G’d will be a judge, and He can examine to see if I did not fulfill my vow to the best of my ability. The letter ו at the beginning of the word והיה, [where we would perhaps have expected Yaakov to use an ordinary future tense such as יהיה, Ed.], may be in lieu of the word הנה, meaning that Yaakov would already from now on act on the assumption that G’d would provide him with the necessities he had asked for and therefore he was willing to be judged by the attribute of Justice, not relying on the attribute of Mercy.