Deuteronomy 4:29
27 Then the Lord will scatter you among the peoples and there will be very few of you among the nations where the Lord will drive you. 28 There you will worship gods made by human hands—wood and stone that can neither see, hear, eat, nor smell. 29 But if you seek the Lord your God from there, you will find him, if, indeed, you seek him with all your heart and soul. 30 In your distress when all these things happen to you in future days, if you return to the Lord your God and obey him 31 (for he is a merciful God), he will not let you down or destroy you, for he cannot forget the covenant with your ancestors that he confirmed by oath to them.
Matthew 7:7
5 You hypocrite! First remove the beam from your own eye, and then you can see clearly to remove the speck from your brother’s eye. 6 Do not give what is holy to dogs or throw your pearls before pigs; otherwise they will trample them under their feet and turn around and tear you to pieces. 7 “Ask and it will be given to you; seek and you will find; knock and the door will be opened for you. 8 For everyone who asks receives, and the one who seeks finds, and to the one who knocks, the door will be opened. 9 Is there anyone among you who, if his son asks for bread, will give him a stone?
Notes and References
"... Having been duly entrusted and warned, the listeners are ready to approach the Father. They are told that if they will, one at a time, ask, seek, and knock (in other words, when a threefold petition is made), “it shall be opened to [them]” (Matthew 7:7). Each one must ask, and each one (pas) who asks, having reached this point, will receive and be received (see Matthew 7:8). Here again, the theme of seeking God, as well as another instance of triadic intonation, is reencountered in the Sermon. The admonition to seek (zēteite) God is salient in the Psalms. Psalms 69:32 invites, “Let the oppressed see it and be glad; you who seek God, let your hearts revive (ekzētēsanta ton theon, kai zēsesthe).” Using Psalms 105:4, “seek the Lord and his strength, seek his presence continually!” as illustrative, Guelich comments that “to seek occurs frequently in the Old Testament with God and his will as the object.” (See, for example, Deuteronomy 4:21; 1 Chronicles 16:10; 22:19; 2 Chronicles 11:16; 12:14; Psalm 34:10; 77:2; 105:3) ..."
Welch, John W. The Sermon on the Mount in the Light of the Temple (p. 170) Ashgate, 2009