What is the ONE THING that we are all to "think to same" about?

This question, beloved soul, comes from this joyous context:

"...fulfill my joy, that you think the same, having the same love, one in soul, MINDING THE ONE THING, doing nothing according to party spirit or self-glory, but in humility, esteeming one another as surpassing themselves; each not looking at the things of themselves, but each also the things of others. For think this within you, which mind was also in Christ Jesus, who subsisting in the form of God, thought it not robbery to be equal with God, but emptied Himself, taking the form of a slave, having become in the likeness of men and being found in fashion as a man, He humbled Himself, having become obedient until death, even the death of a cross. Because of this also God highly exalted Him and gave Him a name above every name, that at the name of Jesus "every knee should bow," of heavenly ones, and earthly ones, and ones under the earth, and "every tongue should confess" that Jesus Christ is "Lord," to the glory of God the Father. Isa. 45:23 So, then, my beloved, even as you always obeyed, not as in my presence only, but now much rather in my absence, cultivate your salvation with fear and trembling, for it is God who is working in you both to will and to work for the sake of His good pleasure.

(Philippians 2:2-13 LITV)

Bonus Q: Could this "ONE THING" which the Apostle writes of by the Spirit, also be the same "ONE THING" that David also wrote of by the same Spirit of Grace and Truth?