וַיֹּ֤אמֶר יְהֹוָה֙ אֶֽל־יַעֲקֹ֔ב שׁ֛וּב אֶל־אֶ֥רֶץ אֲבוֹתֶ֖יךָ וּלְמוֹלַדְתֶּ֑ךָ וְאֶֽהְיֶ֖ה עִמָּֽךְ׃
Then יהוה said to Jacob, “Return to your ancestors’ land—where you were born—and I will be with you.”
Genesis 31:3 (The Contemporary Torah, JPS 2006)
וְהִנֵּ֨ה אָנֹכִ֜י עִמָּ֗ךְ וּשְׁמַרְתִּ֙יךָ֙ בְּכֹ֣ל אֲשֶׁר־תֵּלֵ֔ךְ וַהֲשִׁ֣בֹתִ֔יךָ אֶל־הָאֲדָמָ֖ה הַזֹּ֑את כִּ֚י לֹ֣א אֶֽעֱזׇבְךָ֔ עַ֚ד אֲשֶׁ֣ר אִם־עָשִׂ֔יתִי אֵ֥ת אֲשֶׁר־דִּבַּ֖רְתִּי לָֽךְ׃
Remember, I am with you: I will protect you wherever you go and will bring you back to this land. I will not leave you until I have done what I have promised you.”
Genesis 28:15 (The Contemporary Torah, JPS 2006)
The rabbis make it clear, running Genesis 31:3 in parallel to Genesis 28:15: this verse is not conditional. It is not saying "IF you return, THEN I will be be with you." God has already told Jacob that He *WILL* be with him, and this is a restatement of the Promise God has already made.