We delight in the embrace of a child, our pets, the gathering of family, even in things and hobbies. 

But what delights the heart of God?  Here in his verse we learn that its the communion He has with the hearts of His children.

“The sacrifice of the wicked is an abomination to the Lord: but the prayer of the upright is His delight.” (Proverbs 15:8)

The "sacrifice of the wicked" here  is the religious or seemingly virtuous doings of those who really don't trust in the Lord. There is no fooling Him since Lord knows the heart of every person, knowing "the thoughts and intents of the heart" (Heb 4:12).  These then are the "wicked" in God's eyes. They are the lost who seek to worship or give to the Lord apart from saving faith and trust in His Son, Jesus Christ. They are the 'self-righteous' who do these things, essentially, on their own terms, they cannot thereby please the Lord. 

Oh, but when God’s redeemed children come to Him with an honest trusting heart, in thanksgiving and dependence, this is His delight.  He created us for such fellowship with Him. He longs for your relationship with Him to be honest, vibrant and continual... He is as close as our breath.  Each of us can express our loving trust in Him, delighting the heart of God daily, by making time to be with Him in prayer, not so much the prayers of petitioning, but in honest, heartfelt, communion with Him.