Falling down before - i. e., Yielding and cringing. To see this instead of stedfastness, is as grievous as for the traveler to find the spring at which he hoped to quench his thirst turbid and defiled.
SDA Bible Commentary (limited)
Volume 1-7
26. A troubled fountain. The righteous man should be a spring of water welling up to eternal life (Prov. 10:11; John 4:14); but when he fails to stand up for right and truth before unbelievers and opponents, he becomes a spring trampled by defiling feet until the water is muddied and spoiled. None will be attracted to drink from such a fountain, and they would find little refreshment from it if they were. With the promise of God’s presence for support at all times (Isa. 51:12; Matt. 28:20), it is a disgrace for a believer to lower his colors through moral cowardice.