What is man, that thou art mindful of him? and the son of man, that thou visitest him?
Psalm 8:4
So what is man?
The creation of God which was made in his image. And God’s image is Jesus: Who is the image of the invisible God, the firstborn of every creature – Colossians 1:15
For what purpose was man created?:
Thou art worthy, O Lord, to receive glory and honour and power: for thou hast created all things, and for thy pleasure they are and were created. – Rev 4:11
Now, the question of God’s mindfulness towards man, points us to when God was manifest in flesh. We know this because in Hebrews & in Psalms, after speaking on being mindful, God goes on to talk about “the son of man” being made a little lower than the angels:
But one in a certain place testified, saying, What is man, that thou art mindful of him? or the son of man, that thou visitest him? [7] Thou madest him a little lower than the angels; thou crownedst him with glory and honour, and didst set him over the works of thy hands:
Hebrews 2:6-7 KJVS
God knew the path man would take and the work of redemption he would do, as the son of man, when he would be made lower than the angels to do the work of the cross

Known unto God are all his works from the beginning of the world.
Acts 15:18
Now while the above tells us what God did in his mindfulness, it does not tell us why? I could be “mindful” of someone and send them greetings, pay them a visit, buy them a Dairy Queen banana spilt… but in His mindfulness, God laid down his life to save ours and scripture tells us why:
1 John 3:16 Hereby perceive we the love of God, because he laid down his life for us: and we ought to lay down our lives for the brethren.
Now to the question of Psalm 8 and how it concerns|testifies Jesus: What is man, that thou art mindful of him? and the son of man, that thou visitest him?
We already saw that Jesus’s manifestation in flesh and subsequent death on the cross is God being mindful of us. We saw that love is the reason for it.
But final question?
What is man to be mindful of man at all?
In our eyes, we are nothing compared to him and indeed we aren’t. But he declares us to be his bride: For thy Maker is thine husband – Isaiah 54:5
And as Adam was not deceived but chose to eat, knowing he would die, but did so anyway for his wife sake. So to, Christ chose to die, no one took his life, he chose to die for his bride’s sake.
God chooses to love us! Not because we gave him reason to, but he chooses to because it is who he is.