From Divine Intimacy by Fr. Gabriel of St. Mary Magdalen, O.C.D.,
#154, THE GOOD SHEPHERD
In truth, Jesus could well repeat to each one of us: “What more could I have done for you that I have not done?” (cf. Is 5:4). Oh, would that our generosity in giving ourselves to Him had no limits, after the pattern of His own liberality in giving Himself to us!
“O good Lord Jesus Christ, my sweet Shepherd, what return shall I make to You for all that You have given me? What shall I give You in exchange for Your gift of Yourself to me? Even if I could give myself to You a thousand times, it would still be nothing, since I am nothing in comparison with You. You, so great, have loved me so much and so gratuitously, I who am so small, so wicked and ungrateful! I know, O Lord, that Your love tends toward the immense, the infinite, because You are immense and infinite. Please tell me, O Lord, who I ought to love You.
“My love, O Lord, is not gratuitous, it is owed You…. Although I cannot love You as much has I should, You accept my weak love. I can love You more when You condescend to increase my virtue, but I can never give You what You deserve. Give me then, Your most ardent love by which, with your grace, I shall love You, please You, serve You, and fulfill Your commands. May I never be separated from You, either in time or in eternity, but abide, united to You in love, forever and ever: (Ven R. Jourdain).
I've reposted this before I realized I'd posted it before. This time, what I have realized is that although we are not capable of gratuitously returning love to God who has gratuitously loved us who did not merit His love, we can "walk in His way" by gratuitously loving those who do not merit our love. (Love the Lord your God... (not gratuitous, but owed) and your neighbor (gratuitously, as God does).