ei śloka kahiyāchena rādhā-ṭhākurāṇī
tāṅra kṛpāya sphuriyāche mādhavendra-vāṇī
ei—this; śloka—verse; kahiyāchena—has spoken; rādhā-ṭhākurāṇī—Śrīmatī Rādhārāṇī; tāṅra—Her; kṛpāya—by the mercy; sphuriyāche—has manifested; mādhavendra—of Mādhavendra Purī; vāṇī—the words.
Actually this verse was spoken by Śrīmatī Rādhārāṇī Herself, and by Her mercy only was it manifest in the words of Mādhavendra Purī.
Link to this page: https://prabhupadabooks.com/cc/madhya/4/194