Let us delight in prayer. God loves a cheerful giver in alms, and a cheerful petitioner in prayer. God would have his children free with him. He takes special notice of a spiritual frame, “who hath engaged his heart?” Jer. 30:21. The more delight we have in God, the more delight he will have in us. He takes no pleasure in a lumpish service. It is an uncomely sight to see a joyful sinner and a lumpish petitioner. Why should we not exercise as much joy in holy duties, as formerly we did in sinful practices? How delightfully will men sit at their games, and spend their days in gluttony and luxury? And shall not a Christian find much more delight in applying himself to God? We should delight that we can, and have hearts to ask such gifts, that thousands in the world never dream of begging. To be dull, is a discontentedness with our own petitions. Delight in prayer is the way to gain assurance. To seek God, and treat him as our chiefest good, endears the soul to him. Delighting in accesses to him, will enflame our love. And there is no greater sign of an interest in him than a powerful estimation of him. God casts off none that affectionately clasp about his throne.
–Excerpt from here.