These are lines from the great Hindi poet Surdas.
Udho ( Uddhav ) represent reason, while the gopis of Vrindavan represent emotion.
Udho was a close friend of Lord Krishna, and Lord Krishna was very fond of him.
The gopis of Vrindavan had given their hearts to Lord Krishna. But Udho said to Lord Krishna, who was then in Mathura ( which is 18 kms. from Vrindavan ), that he should tell them to forget him.
At one time, no doubt, the gopis had an infatuation for Krishna. But now they had grown up, and would soon be married, and have families of their own. So they should now get over that infatuation and forget him.
At this, Lord Krishna smiled, and said that he ( Udho ) should himself go as Krishna's messenger, and convey this message to the gopis.
This is the reply the gopis gave to Udho when he met them in Vrindavan.