When we give our heart to the Lord and receive the born-again life, there is overwhelming joy in our hearts, and rightly so! For the life with the Lord is a joyful life.
Yet, that does not mean God will not discipline us. The Lord calls us to Him in His great love, and leads us into the wilderness and there He wants to speak with us. In the Bible ‘the wilderness’ always means a barren and difficult time full of trials and temptations. Just read the history of Israel: there was no shortage of grumbling and rebellion! But the Lord wants to educate us and therefore He takes us aside to speak to us tenderly.
How stupid we are to rebel against the trials by which God wants to educate us, transform us into His image (2 Corinthians 3:18) because He loves us. He wants to make us into the bride of Christ, to bring us very close to Him. Therefore our hearts must be purified of all idols, of all wrong ties, of everything that is not of the Lord. This purification hurts, but in His great love the Lord will not discipline us any longer than strictly necessary. He will not let us be tempted beyond what we can bear.
When we are purified like this, we will notice ever more how the joy we had in the beginning - when we got to know Him - will become much more profound. Let us, therefore, devote ourselves entirely to Him, become attached to Him, until we are united with the Lord and are one with Him in Spirit (1 Corinthians 6:17).