Nowhere in the Bible is artificial birth control condemned. In fact it is not even mentioned.
(Onins sin was disobeying Gods order to get his sister-in-law pregnant, not for merely wasting his seed. The sin here would have been the same if he had refused to go into her in the first place.)
The basis of the Churches stance on condoms and birth control are based on two edicts.
The Casti Connubi of 1930 ". . . any use whatsoever of matrimony exercised in such a way that the act is deliberately frustrated in its natural power to generate life is an offense against the law of God and of nature, and those who indulge in such are branded with the guilt of a grave sin"
The Humanae Vitae of 1968 "man does not have unlimited dominion over his body in general, so also, and with more particular reason, he has no such dominion over his specifically sexual faculties, for these are concerned by their very nature with the generation of life, of which God is the source."
These are Church Laws, not biblical laws of the New Testament.
Can a Church Law, or Canon, be reversed, or dropped if seen as no longer applicable, unjustified, or misguided?
Yes!
The Dum Diversas "We grant you [Kings of Spain and Portugal] by these present documents, with our Apostolic Authority, full and free permission to invade, search out, capture, and subjugate the Saracens and pagans and any other unbelievers and enemies of Christ wherever they may be, as well as their kingdoms, duchies, counties, principalities, and other property [...] and to reduce their persons into perpetual slavery."
The Romanus Pontifex "-- to invade, search out, capture, vanquish, and subdue all Saracens and pagans whatsoever, and other enemies of Christ wheresoever placed, and the kingdoms, dukedoms, principalities, dominions, possessions, and all movable and immovable goods whatsoever held and possessed by them and to reduce their persons to perpetual slavery, and to apply and appropriate to himself and his successors the kingdoms, dukedoms, counties, principalities, dominions, possessions, and goods, and to convert them to his and their use and profit --"
And the Inter caetera "Among other works well pleasing to the Divine Majesty and cherished of our heart, this assuredly ranks highest, that in our times especially the Catholic faith and the Christian religion be exalted and be everywhere increased and spread, that the health of souls be cared for and that barbarous nations be overthrown and brought to the faith itself. ..."
These last three papal edicts led to war, colonialism, and slavery. Are they in effect today? No.
The Church has issued many misguided edicts, bulls, and canons that are no longer in effect today.
The Ad Exstirpanda set down rules for the torture of heretics, then Pope Alexander IV allowed absolution of those clerics who went to far in their torture.
So you see, as times and circumstances have changed, so has the Churches policies. Times have changed. Condoms help in the prevention of a terrible disease. If the Church refuses to reverse this policy, it, and the Pope, are responsible for the deaths of millions.
The past Church doctrines of war, slavery, colonialism and torture are an embarrassment to the Catholic religion, lets stop this injustice now.