Upholding God's holiness

“This is because both of you broke faith with me in the presence of the Israelites at the waters of Meribah Kadesh in the Desert of Zin and because you did not uphold My holiness among the Israelites.” Deuteronomy 32:50-51
At face value, the events that led to God denying Moses entry into the Promised Land seem to be rather innocuous. Was this unfair of God, to deny Moses what he had been longing for all his life – especially after all that he had had to put up with in leading the Israelites through the desert for forty years: the grumbling, the complaining, the wailing, the lack of faith?
Twice in the wilderness wanderings, the Israelites camped in a place where there was no water, and God miraculously provided water for them from a rock. The first time, He commanded Moses to strike the rock, and water came forth (Ex. 17). The second time, He commanded Moses to speak to the rock (Num. 20). But Moses, in his frustration, struck the rock, and although the water came forth, God took Moses aside and said because of this he would not enter the Promised Land.
In this verse God gives us the real reason why Moses was not allowed to enter: because he failed to uphold God’s holiness. While Moses was angry at the people for their unbelief, God was not. He was simply leading them to another place where they would have to trust Him to provide. Because of His mercy, He caused water to come from the rock a second time, even when it was struck instead of being spoken to. God would surely have been glorified if Moses had spoken to the rock and water had come forth; as it was, the event was merely a repeat of the first time in the eyes of the people.
This is a sobering thought for us: How often do we miss out on the things we long for, because we fail to uphold God’s holiness in the sight of those around us?