C. F. Keil and Franz Delitzsch on Ezra 1:6

Ezr 1:6

All their surrounders assisted them with gifts. The surrounders are the people of the places where Jews were making preparations for returning; chiefly, therefore, their heathen neighbours (Ezr 1:4), but also those Jews who remained in Babylon. חזּקוּ בידיהם is not identical in meaning with יד חזּק, to strengthen, e.g., Jer 23:14; Neh 2:18; but with החזיק בּיד, the Piel here standing instead of the elsewhere usual Hiphil: to grasp by the hand, i.e., to assist; comp. Lev 25:34. על לבד, separated to, besides; elsewhere joined with מן, Exo 12:37, etc. התנדּב connected with כּל without אשׁר, as the verbum fin. in Ezr 1:5, 1Ch 29:3, and elsewhere. האלהים לבית must, according to Ezr 1:4, be supplied mentally; comp. Ezr 2:68; Ezr 3:5; 1Ch 29:9, 1Ch 29:17.