Abraham 2 - 5; JS-M

In a vision given to the Prophet Joseph Smith in the Kirtland Temple, he -

"...beheld the celestial kingdom of God, and the glory thereof...[and] the transcendent beauty of the gate through which the heirs of that kingdom [would] enter, which was like unto circling flames of fire; Also the blazing throne of God, whereon was seated the Father and the Son...
[and] the beautiful streets of that kingdom, which had the appearance of being paved with gold.
(Doctrine and Covenants Section 137:1 - 4)

He saw Adam, Abraham, his father and mother, and his brother Alvin which he said had "long since slept". And the prophet -

"...marveled how it was that he had obtained an inheritance in that kingdom, seeing that he had departed this life before the Lord had set his hand to gather Israel the second time, and had not been baptized for the remission of sins..." (Doctrine and Covenants Section 137:6)

And the voice of the Lord came to him saying -

"...All who have died without a knowledge of this gospel, who would have received it if they had been permitted to tarry, shall be heirs of the celestial kingdom of God..." (Doctrine and Covenants Section 137:8 - 7)

And also -

"..all that shall die henceforth without a knowledge of it, who would have received it with all their hearts, shall be heirs of that kingdom..." (Doctrine and Covenants Section 137:8)

For the Lord explains -

I...will judge all men according to their works, according to the desire of their hearts..." (Doctrine and Covenants Section 137:9)

As I've read and pondered this revelation, I have come to the conclusion and the Lord is omnipotent and knows all truth for -

"...truth is knowledge of things as they are, and as they were, and as they are to come..."
(Doctrine and Covenants Section 93:2)

Therefore he already knows if we obey his commandments and keep our second estate.

Abraham had the great privilege of having a vision of our pre-existent life, our first estate, where the Lord revealed that -

"...he said unto those who were with him: We will go down, for there is space there, and we will take of these materials, and we will make an earth whereon these may dwell;
25 And we will prove them herewith, to see if they will do all things whatsoever the Lord their God shall command them;
26 And they who keep their first estate shall be added upon; and they who keep not their first estate shall not have glory in the same kingdom with those who keep their first estate; and they who keep their second estate shall have glory added upon their heads for ever and ever.
(Pearl of Great Price Abraham 3:24 - 26)

I've come to the opinion because the Lord knows all truth, and already knows the desire of our hearts, the the proving as "we will prove them herewith" maybe just our own proving to ourselves in the final decisions, justice, and judgements of the Lord.