Valmiki Ramayana Sundara Kanda Sarga 1 Shloka 84
Original Shlokaतताप न हि तं सूर्यः प्लवन्तं वानरोत्तमम्। सिषेवे च तदा वायू रामकार्यार्थसिद्धये।।5.1.84।।
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तदा then, प्लवन्तम् while he was leaping, तं वानरोत्तमम् that best of vanaras, सूर्यः Sun, रामकार्यार्थसिद्धये for accomplishing Rama's task, न हि तताप did not discharge heat, वायुः च and even wind, सिषेवे served cool.
The Sun spared Hanuman from the heat and even the Windgod served him, blowing cool while he was taking leaps in order to fulfil Rama's mission.