God is infinitely self-sufficient; He doesn’t need our worship or our service. He is perfectly complete and content in Himself.
Even so, there is something God lacks, which He may only obtain through us: affliction. (Col 1:24) God would not afflict Himself, or cause Himself grief or suffering: this only comes to Him through sin.
This suffering in God is not at all for God; it is for us; it is the vehicle through which God chooses to reveal His infinite nature and character to the universe (Ro 9:22-23), and the elect are the primary beneficiaries of this.
And it may very well be that the primary way God suffers is by allowing His children to suffer innocently at the hands of the wicked. When believers are persecuted, Jesus Christ takes it personally, as if He Himself were being persecuted. (Ac 9:4) This is a gift He gives Himself through us and for us, and also a deep privilege he bestows upon us. (Php 1:29)
Perhaps it is only in this mindset that we fully rejoice in difficulty (Ja 1:2) and tribulation (Ro 5:3): suffering not only works patience and holiness in us (He 12:10-11), but will eventually serve to glorify God immensely. (1Pe 1:6-7) If God is allowing others to afflict Himself through us, for a glorious eternal purpose, we can glory in this as well for His sake. (Php 3:10)
There’s something about God’s suffering that will vindicate and glorify Him one day. The nature of His enemies will be open to the universe, impossible to hide, since He’s given them liberty to pursue their own free will. Most all of what they have done will have been perpetrated against His own, whom the world hates because it hates Him. (Jn 15:19) In that day, in the context of the suffering of God, there will be no just complaints, no excuse for the wicked. (Ro 1:20)
Let’s be ready and willing to suffer for God as He wills (Ga 6:14), to let Him suffer in and through us. (Ga 2:20) This light affliction, for a moment, works for us a far more exceeding and eternal weight of glory. (2Co 4:17)