Is Thomas 3 an Echo of Deuteronomy?
I suggest that the first part of saying 3 in the Gospel of Thomas (3a) be considered as a likely echo of Deuteronomy 30:11-14.
A recurring stress in the Gospel of Thomas is the immediacy of the Kingdom: the Kingdom is not something to be waited for in the future or found elsewhere. Rather it is already present and possible of attainment here. Saying 3a states it as follows:
Jesus said: If your leaders say to you "Look! The Kindgom is in the sky!" then the birds will be there before you are. If they say that the Kingdom is in the sea, then the fish will be there before you are. Rather, the Kingdom is within you and it is outside of you.
In Thomas Jesus is the figure not so much inaugurating the Kindom as introducing it. Similarly, for the writers of the latter books of the Pentateuch, Moses is the figure who introduces the Law. In Deuteronomy 30, Moses stresses that the Law is not something one must search for; rather the people have it already at their disposal because God has given it to them. The text reads as follows:
For this commandment which I command thee this day, it is not hidden from thee, neither is it far off. It is not in heaven, that thou shouldest say, Who shall go up for us to heaven, and bring it unto us, that we may hear it, and do it? Neither is it beyond the sea, that thou shouldest say, Who shall go over the sea for us, and bring it unto us, that we may hear it, and do it? But the word is very nigh unto thee, in thy mouth, and in thy heart, that thou mayest do it. (30:11-14)
The saying in Thomas and Moses' exhortation in Deuteronomy are strikingly parallel in several important respects. First, they thematize distance by evoking first heaven (in Thomas: the sky), then the sea as the places that need not be crossed or visited to attain what is most desirable: the Law for Moses; the Kingdom for Jesus. Second, they contrast these distances with the closeness of that which is already "within you": the Law is within you, the Kingdom is within you. Rhetorically, the structure of the two sayings is identical. But thematically also, they are nearly identical. One may say in fact that there is no place in the Pentateuch that comes closer thematically to this major stress in Thomas: the nearness, the already inwardness, of the greatest spiritual good.
I would suggest the strong possibility that the Thomas saying is a conscious echo of the verses in Deuteronomy.
NB: The above-quoted saying from Thomas is in Stevan Davies' translation.
Correction: April DeConick has informed me that I am most likely right here, but that the parallel with the text in Deuteronomy had already been noted, for instance by J.E. Menard. I should get a copy of her recent, thoroughly annoted translation.