A Commentary, Critical, Practical, and Explanatory on the Old and New Testaments, by Robert Jamieson, A.R. Fausset and David Brown  at sacred-texts.com
exo 31:2BEZALEEL AND AHOLIAB. (Exo. 31:1-18)
See, I have called--Though the instructions about the tabernacle were privately communicated to Moses, it was plainly impossible that he could superintend the work in person, amid the multiplicity of his other duties. A head director or builder was selected by God Himself; and the nomination by such high authority removed all ground of jealousy or discontent on the part of any who might have thought their merits overlooked (compare Mat 18:1).
by name Bezaleel--signifying "in the shadow or protection of God"; and, as called to discharge a duty of great magnitude--to execute a confidential trust in the ancient Church of God, he has his family and lineage recorded with marked distinction. He belonged to the tribe of Judah, which, doubtless for wise and weighty reasons, God all along delighted to honor; and he was the grandson of Hur, a pious patriot (Exo 17:12), who was associated, by a special commission, with Aaron in the government of the people during the absence of Moses. Moreover, it may be noticed that a Jewish tradition affirms Hur to be the husband of Miriam; and if this tradition may be relied on, it affords an additional reason for the appointment of Bezaleel emanating from the direct authority of God.
exo 31:3I have filled him with the spirit of God--It is probable that he was naturally endowed with a mechanical genius, and had acquired in Egypt great knowledge and skill in the useful, as well as liberal, arts so as to be a first-class artisan, competent to take charge of both the plain and ornamental work, which the building of the sacred edifice required. When God has any special work to be accomplished, He always raises up instruments capable of doing it; and it is likely that He had given to the son of Uri that strong natural aptitude and those opportunities of gaining mechanical skill, with an ultimate view to this responsible office. Notwithstanding that his grand duty was to conform with scrupulous fidelity to the pattern furnished, there was still plenty of room for inventive talent and tasteful exactness in the execution; and his natural and acquired gifts were enlarged and invigorated for the important work.
exo 31:6I have given with him Aholiab--He belonged to the tribe of Dan, one of the least influential and honorable in Israel; and here, too, we can trace the evidence of wise and paternal design, in choosing the colleague or assistant of Bezaleel from an inferior tribe (compare Co1 12:14-25; also Mar 6:7).
all that are wise-hearted I have put wisdom--At that period, when one spirit pervaded all Israel, it was not the man full of heavenly genius who presided over the work; but all who contributed their skill, experience, and labor, in rendering the smallest assistance, showed their piety and devotedness to the divine service. In like manner, it was at the commencement of the Christian Church (Act 6:5; Act 18:2).
exo 31:12Verily my sabbaths ye shall keep--The reason for the fresh inculcation of the fourth commandment at this particular period was, that the great ardor and eagerness, with which all classes betook themselves to the construction of the tabernacle, exposed them to the temptation of encroaching on the sanctity of the appointed day of rest. They might suppose that the erection of the tabernacle was a sacred work, and that it would be a high merit, an acceptable tribute, to prosecute the undertaking without the interruption of a day's repose; and therefore the caution here given, at the commencement of the undertaking, was a seasonable admonition.
exo 31:18tables of stone, written with the finger of God--containing the ten commandments (Exo 24:12), called "tables of testimony," because God testified His will in them.