Abram and Sarai

1 Peter 3:5-6 (KJV) For after this manner in the old time the holy women also, who trusted in God, adorned themselves, being in subjection unto their own husbands:
Even as Sara obeyed Abraham, calling him lord: whose daughters ye are, as long as ye do well, and are not afraid with any amazement.

The way I understand this, Peter is using Sarah as an example of demonstrating obedience to God through obedience to husband.

 

Hebrews 11:8-11 NASB95 By faith Abraham, when he was called, obeyed by going out to a place which he was to receive for an inheritance; and he went out, not knowing where he was going. By faith he lived as an alien in the land of promise, as in a foreign land, dwelling in tents with Isaac and Jacob, fellow heirs of the same promise; for he was looking for the city which has foundations, whose architect and builder is God. By faith even Sarah herself received ability to conceive, even beyond the proper time of life, since she considered Him faithful who had promised.

Agree with Jon, obedience and faithfulness are linked.
When her faith began isn't a part of the biblical story.

Rob

 

The assault on the institution of marriage was complete here in the USA on June 26, 2015 when the SCOTUS declared the abomination of "marriage" based on sodomy.

Likewise the abomination of the murder of innocent life on January 22, 1973 (Roe v. Wade).

Luke 17
28 Likewise also as it was in the days of Lot; they did eat, they drank, they bought, they sold, they planted, they builded;
29 But the same day that Lot went out of Sodom it rained fire and brimstone from heaven, and destroyed them all.
30 Even thus shall it be in the day when the Son of man is revealed.

Matthew 16
The Pharisees also with the Sadducees came, and tempting desired him that he would shew them a sign from heaven.
2 He answered and said unto them, When it is evening, ye say, It will be fair weather: for the sky is red.
3 And in the morning, It will be foul weather to day: for the sky is red and lowring. O ye hypocrites, ye can discern the face of the sky; but can ye not discern the signs of the times?
4 A wicked and adulterous generation seeketh after a sign; and there shall no sign be given unto it, but the sign of the prophet Jonas. And he left them, and departed.

 

Hebrews 11:11-16 KJB
Through faith also Sara herself received strength to conceive seed, and was delivered of a child when she was past age, because she judged him faithful who had promised.
Therefore sprang there even of one, and him as good as dead, so many as the stars of the sky in multitude, and as the sand which is by the sea shore innumerable.
These all died in faith, not having received the promises, but having seen them afar off, and were persuaded of them, and embraced them, and confessed that they were strangers and pilgrims on the earth.
For they that say such things declare plainly that they seek a country.
And truly, if they had been mindful of that country from whence they came out, they might have had opportunity to have returned.
But now they desire a better country, that is, an heavenly: wherefore God is not ashamed to be called their God: for he hath prepared for them a city.