וַיִּֽזְרַֽח־ל֣וֹ הַשֶּׁ֔מֶשׁ כַּאֲשֶׁ֥ר עָבַ֖ר אֶת־פְּנוּאֵ֑ל וְה֥וּא צֹלֵ֖עַ עַל־יְרֵכֽוֹ׃
און די זון איז אים אױפֿגעגאַנגען װי ער איז אַריבערגעגאַנגען פּניאֵל. און ער האָט געהונקען אױף זײַן דיך.
Rashi
ויזרח לו השמש AND THE SUN SHONE UPON HIM— This is the expression that people use: “When we reached such-and-such a place the dawn broke upon us”. This is its literal sense. But the Midrash says that לו means, “for his needs” — to heal his lameness. Thus, too, you read in Scripture a similar metaphor (Malachi 3:20) “the sun of righteousness with healing in its wings”. The hours that it had set before its time for his sake when he left Beer-Sheba (cp. Genesis 18:11) it now rose before its time for his sake (Sanhedrin 75b).
Chizkuni
ויזרח לו השמש, “the sun shone for him.” In the In the Western hemisphere, the sun’s rays rise earlier and became stronger on a daily basis starting in the month of Tevet, until in the month of Tammuz the days again start to become shorter and the sun’s rays weaker. Our author tries to show how the season’s variations are hinted at in the words of the Torah here. The reason why the author does this is because he was troubled by the Torah in our verse making it appear as if the sun shone only for Yaakov and not the rest of the world. He uses the numerical value of the word: 36=לו, as the basis of this exegesis. [I have decided to omit the details of this astronomical part of his exegesis of this verse. Ed.]
Rashbam
והוא צולע על ירכו, now that the sun was shining he realised that he was walking with a limp, a belated discovery, just as when he discovered that he had spent a night in bed with Leah thinking that she was Rachel (29,25).