The Bible

Even though he may tarry, wait for him
(Habakuk 2:3)

Therefore wait for Me, said G-d, for the day when I will stand up to bear witness. For then I will change the nations to speak a clear language, so that they all call in the name of the L-rd and join shoulders to serve Him.
(Zefaniah 3:8-9).

“For there is yet a prophecy for a set term, and this prophet will speak of the end, and not lie. Even if it tarries, wait for it still; For it will surely come, without delay.”
(Habakuk 2:3)

“Truly, the L-RD is waiting to show you kindness, Truly, He will arise to pardon you. For the L-RD is a G-d of justice; fortunate are all who wait for Him.”
(Isaiah 30:18)

Our souls waited for the L-RD, He is our help and shield.
(Psalms 33:20)

So I will wait for the L-RD, who is hiding His face from the House of Jacob, and I will trust in Him.
(Isaiah 8:17)

Happy is the one who waits and reaches one thousand three hundred and thirty-five days.
(Daniel 12:12)

The L-rd is good to those who hope for Him, to the soul who seeks Him.
(Lamentations 3:25)

And there is hope for your end, said the L-rd – the children shall return to their borders.
(Jeremiah 31:16)

The L-rd is the hope of Israel.
(Jeremiah 17:13)

Are You not the L-rd our G-d? and we will hope to You.
(Jeremiah 14:22)

And he will say on that day, behold this is our G-d, we hoped to Him that He should save us. This is the L-rd to Whom we hoped, let us rejoice and be happy in His salvation.
(Isaiah 25:9)

Do not say, “I will pay back evil.” Hope to the L-rd and He will save you.
(Proverbs 20:22)

No eye saw but Yours, O G-d, what You are making for those who await You.
(Isaiah 64:3)

The Midrash

“Therefore wait for Me, said G-d, for the day when I will stand up to bear witness.” Said the Holy One, blessed is He: I swear that whoever waits for My kingdom, I myself will bear witness in his favor.
(Yalkut Shimoni 567)

Rambam, Known as Maimonides, foremost codifier of Jewish law (1138-1204)
I believe with perfect faith in the coming of the messiah, and although he may tarry, I will await his coming every day.
(Thirteen Principles of Faith)