The bible says that Israel served the Lord all the days of Joshua, and for years after he died.
Joshua 24
31 And Israel served the Lord all the days of Joshua, and all the days of the elders that overlived Joshua, and which had known all the works of the Lord, that he had done for Israel.
"All the days of (fill in the blank)" is a Hebrew idiom for the time a ruler was over the nation. Not to be confused with "all the days of his/her/their/etc life", which is an idiom for a persons life from birth to death. In Joshua's case, his "days" began when he took over command from Moses (Joshua 1:1-10). You will not find a SINGLE example of ANYONE serving other gods under Joshuas command. What you will find is the people accepting Joshua as their leader (Josh 1:16-18), and the bible REPEATING the truth concerning their fidelity to God:
Judges 2
7 And the people served the Lord all the days of Joshua, and all the days of the elders that outlived Joshua, who had seen all the great works of the Lord, that he did for Israel.
No one who served other Gods made it to the promised land.
Joshua 5
6 For the children of Israel walked forty years in the wilderness, till all the people that were men of war, which came out of Egypt, were consumed, because they obeyed not the voice of the Lord: unto whom the Lord sware that he would not shew them the land, which the Lord sware unto their fathers that he would give us, a land that floweth with milk and honey.
Numbers14
28 Say unto them, As truly as I live, saith the Lord, as ye have spoken in mine ears, so will I do to you:
29 Your carcases shall fall in this wilderness; and all that were numbered of you, according to your whole number, from twenty years old and upward which have murmured against me.
30 Doubtless ye shall not come into the land, concerning which I sware to make you dwell therein, save Caleb the son of Jephunneh, and Joshua the son of Nun.
31 But your little ones, which ye said should be a prey, them will I bring in, and they shall know the land which ye have despised.
Numbers 32
11 Surely none of the men that came up out of Egypt, from twenty years old and upward, shall see the land which I sware unto Abraham, unto Isaac, and unto Jacob; because they have not wholly followed me:
It is worth noting in numbers 32 what God said concerning what would happen if those 19 and under made the same mistake as their fathers:
Numbers 32
14 And, behold, ye are risen up in your fathers' stead, an increase of sinful men, to augment yet the fierce anger of the Lord toward Israel.
15 For if ye turn away from after him, he will yet again leave them in the wilderness; and ye shall destroy all this people
Did that happen? Did Israel wander for another 40 years because they turned away from the Lord? No, the bible says they took possession of the land because during the days of Joshua, the people served the Lord.
He didnt make the statement "if it seems evil to serve the Lord" for nothing, out of thin air. A verse earlier, he told them this:
Joshua 24
14 Now therefore fear the Lord, and serve him in sincerity and in truth: and put away the gods which your fathers served on the other side of the flood, and in Egypt; and serve ye the Lord.
Their first choice was to serve the Lord. It doesnt matter that "serve the Lord" came before the word "choose", it is still an option. Serving the Lord is the FIRST option, and if they thats evil in their sight (and he's not saying it is) then they have the option of either the gods their father served on the other side of the river, or one of the gods from the land they now inhabited.
Thats precisely what it is.
Deut 30
15 See, I have set before thee this day life and good, and death and evil;
16 In that I command thee this day to love the Lord thy God, to walk in his ways, and to keep his commandments and his statutes and his judgments, that thou mayest live and multiply: and the Lord thy God shall bless thee in the land whither thou goest to possess it.
17 But if thine heart turn away, so that thou wilt not hear, but shalt be drawn away, and worship other gods, and serve them;
18 I denounce unto you this day, that ye shall surely perish, and that ye shall not prolong your days upon the land, whither thou passest over Jordan to go to possess it.
19 I call heaven and earth to record this day against you, that I have set before you life and death, blessing and cursing: therefore choose life, that both thou and thy seed may live:
God always lays out BOTH life and death. Your morbid rendering suggests He only offered death. That sentiment is rebuked twice already in Joshua 24:31 and Judges 2:7, and verse 15 shows that Joshua did exactly what he knew to do, he chose life:
"as for me and my house, we will serve the Lord"
This is your theology again doing a complete "180" to scripture. The bible does not say that man "cannot" obey the law, it says the polar opposite.
Deut 30
11 For this commandment which I command thee this day, it is not hidden from thee, neither is it far off.
14 But the word is very nigh unto thee, in thy mouth, and in thy heart, that thou mayest do it.
Not only does the bible say that the law isnt too hard for man to keep, or out of our reach, but it is close enough (in our hearts) that we can do/obey it. Beyond that, the bible testifies AGAIN about how the law was able to be kept and obeyed:
Luke 1
6 And they were both righteous before God, walking in all the commandments and ordinances of the Lord blameless.
So how was Zacharias and Elisabeth able to do something you claim man "cannot" do? And why are you dragging Paul into this? He NEVER said we "cannot" obey the law. What he said in Romans 3:20 is no different than what he said several times throughout his epistles: works dont save.
The non biblical portion of your statement has been underlined for your convenience.