Answers to Quora Questions by Yair Davidiy
When Jews pray, do they face east, towards Jerusalem, regardless of where they happen to be, like Jews living in Manchester facing east will not be facing Jerusalem but Kaliningrad?
https://www.quora.com/When-Jews-pray-do-they-face-east-towards-Jerusalem-regardless-of-where-they-happen-to-be-like-Jews-living-in-Manchester-facing-east-will-not-be-facing-Jerusalem-but-Kaliningrad/answer/Yair-Davidiy
The other answers will have already pointed out that the law is that one prays towards Jerusalem and in Jerusalem towards the Temple. This is the prevailing practice. If one does not know which direction to pray in then the intention should be towards the Temple.
King Solomon foresaw that the Israelites would be exiled and his Temple destroyed. He therefore requested that their prayers be heard when they pay in the direction of the Land of Israel and of the Temple even when it would no longer be standing.
1-Kings 8:
48 if they return to You with all their heart and with all their soul in the land of their enemies who have taken them captive, and pray to You toward their landwhich You have given to their fathers, the city which You have chosen, and the house which I have built for Your name; 49 then hear their prayer and their supplication in heaven Your dwelling place, and maintain their cause, 50 and forgive Your people who have sinned against You and all their transgressions which they have transgressed against You, and make them objects of compassion before those who have taken them captive, that they may have compassion on them 51 (for they are Your people and Your inheritance which You have brought forth from Egypt, from the midst of the iron furnace), 52 that Your eyes may be open to the supplication of Your servant and to the supplication of Your people Israel, to listen to them whenever they call to You....
The Jews in Exile were mainly located to the west of the Land of Israel. They may not have always been certain where Jerusalem was but they knew it was somewhere to their east and therefore they prayed towards the east.
[There may even have been something special about the east.] The geographical directions of the Classical Commentators are not always correct. The great Commentator Rashi appears to be always reliable in this matter but there are others of which this cannot be said. By always facing east they would have known that the general direction was right and they would have intended to face the site of the Temple. Nowadays we nearly always do face the correct direction but I guess most of us usually forget about the Temple. Nevertheless, the time will come.
Malachi 3:
4 Then the offering of Judah and Jerusalem will be pleasing to the LORD as in the days of old and as in former years.Ezekiel 40:
2 In the visions of God He brought me into the land of Israel and set me on a very high mountain, and on it to the south there was a structure like a city....5 And behold, there was a wall on the outside of the temple all around...
41:
5 Then he measured the wall of the temple...