His heart is established - לבו סמוך samuch libbo, "his heart is propped up;" he is buttressed up by the strength of his Maker.
His heart is established - Sustained; upheld. This is the same idea, though somewhat varied in form. The word means to sustain; to support; and the idea is, that there is some basis of support - some strength - which is not his own.
He shall not be afraid - When he is assailed by enemies.
Until he see his desire upon his enemies - This implies that he had nothing really to fear. He would certainly overcome his foes; and in the meantime he might look calmly on all their efforts to destroy him, for those efforts would be vain. So the believer now looks calmly on all his spiritual foes. He has nothing to fear, for he will overcome them all; he will certainly triumph; he will trample them all under his feet. He may well, therefore, endure these conflicts for a brief period, for the issue is certain, and the conflict will soon come to an end.