If you'll recall

[sitifan]

If you’ll recall, God gave Abraham a son when he was very, very old.

What does "If you’ll recall" mean?

[chevalier]

- not a teacher -

"if you'll remember"
to recall = to bring back to mind ≈ to remember

[sitifan]

Normally we don't use "will" in conditional claues.
For example, we say "if it rains tomorrow, we'll ..." not "if it will rain tomorrow, we'll ..."
Why use "will" in "if you'll recall"?

[5jj]

It is fine to use 'will', with the idea of volition, in -if clauses.

If you will (are willing to) drive me to the station, I'll be able to catch the early train.

[sitifan]

Dear fivejedjon, do you mean If you'll recall = If you are willing to recall?

[5jj]

Dear fivejedjon, do you mean If you'll recall = If you are willing to recall?

It could mean that. 'If you will/would' can also be used for polite requests.

In your original sentence, it means something along the lines of, "I am gently reminding you of the fact that you don't need reminding of".