“Did Jesus obtain a sinful nature when He was here 2000 years ago? In other words, if He became like one of us in all ways, was His nature the same as ours? Would you please explain.”
The book of Hebrews answers this question quite well. Here we read of Jesus, “I will put my trust in him. And again, Behold I and the children which God hath given me. Forasmuch then as the children are partakers of flesh and blood, he also himself likewise took part of the same; that through death he might destroy him that had the power of death, that is, the devil.” (Hebrews 2:13, 14)
Here the Bible makes it clear that just as the children are partakers of flesh and blood, Christ took part of the same. Who are these children? The Bible tells us they are the children which God has given to Christ. These are the redeemed. It is not speaking here of Adam and Eve before they fell into sin, but of those who have already sinned and been redeemed from their sins.
It is obvious then, that just as you and I are partakers of flesh and blood, Jesus took part of the same—the same flesh and blood that you and I have, not the flesh and blood that Adam and Eve had before they fell.
Continuing on we read, “For verily he took not on him the nature of angels; but he took on him the seed of Abraham.” (Hebrews 2:16)
Here again we see that Christ took on Him the seed of Abraham rather than the nature of Adam before he sinned. Then we read, “Wherefore in all things it behoved him to be made like unto his brethren, that he might be a merciful and faithful high priest in things [pertaining] to God, to make reconciliation for the sins of the people.” (Hebrews 2:17)
Here is an even more conclusive statement. Jesus had to be made in all things like his brethren. We also read that He “was in all points tempted like as we are, yet without sin.” (Hebrews 4:15) If in any point Jesus was not made “like unto his brethren,” then in that point He could not have been “tempted like as we are.” If Jesus did not take upon Him sinful flesh then He could not be tempted like as we are, because we are tempted through our sinful flesh.
Yes, Jesus did obtain a sinful nature when He was here 2000 years ago. I hope this helps to answer your question.