After Joseph was born and the second period of seven years of service was complete, Jacob desired to leave Laban and return to Canaan with his family. Laban replies - "Please stay, if I have found favor in your eyes, for I have learned by experience that the LORD has blessed me for your sake" (Gen. 30:27). Laban asks Jacob to stay and encourages him to state his desired wages since he had labored the prior fourteen years for his two daughters. Jacob answers by observing that Laban had become quite wealthy while Jacob fed and kept his flocks. Jacob had served him very faithfully and Laban knows this. Laban selfishly wants his own prosperity to continue, which is why he doesn't want Jacob to leave. Jacob doesn't want any gifts from Laban's present wealth, but he does proceed to make an intriguing request for how his future wages will be determined - "Let me pass through all your flock today, removing from there all the speckled and spotted sheep, and all the brown ones among the lambs, and the spotted and speckled among the goats; and these shall be my wages. So my righteousness will answer for me in time to come, when the subject of my wages comes before you; every one that is not speckled and spotted among the goats, and brown among the lambs, will be considered stolen, if it is with me" (Gen. 30:32,33). There are some difficult things to understand in this context, but the verses that follow make Jacob's desire clear. From what I understand, sheep are normally white and goats are normally black or dark brown in the Orient. However, occasionally one will be born with speckles and spots. All
of the current flock will continue to be Laban's (since Jacob did not want Laban to give him anything presently; cf. 30:31), but any future animals born with speckles and spots would belong to Jacob. At this point it seems that Jacob is trusting God's providence completely to make him wealthy.
Laban thinks this is a great idea. No doubt he believed he was getting a wonderful bargain since very few of the animals would be born speckled and spotted (or so he thought!). But, Laban's behavior shows distrust by removing the speckled and spotted animals himself and by sending them far away, as the following verses show - "So he [Laban] removed that day the male goats that were speckled and spotted, all the female goats that were speckled and spotted, every one that had some white in it, and all the brown ones among the lambs, and gave them into the hand of his sons. Then he put three days' journey between himself and Jacob, and Jacob fed the rest of Laban's flocks" (Gen. 30:35,36). Laban, after getting Jacob to agree to continue working for him, immediately takes action to try to minimize Jacob's potential for gain. To prevent them from breeding more like themselves among the pure-colored flocks, the current speckled and spotted animals are removed (since they will always be Laban's) and Jacob is left with only pure-colored flocks. Laban thinks this will minimize Jacob's likelihood of becoming prosperous at his expense. In the future it would be easy to tell which animals were Jacob's and which were Laban's among those for which Jacob tended to. When Jacob began his fifteenth year of service with Laban, all the animals he fed and kept belonged to Laban, but such would not be the case for long!