Ki Teitzei: Not Giving Up An Escaped Slave

A curious pasuk in Ki Teitzei, in Devarim 23:16:

טז לֹא-תַסְגִּיר עֶבֶד, אֶל-אֲדֹנָיו, אֲשֶׁר-יִנָּצֵל אֵלֶיךָ, מֵעִם אֲדֹנָיו.	16 Thou shalt not deliver unto his master a bondman that is escaped from his master unto thee;
יז עִמְּךָ יֵשֵׁב בְּקִרְבְּךָ, בַּמָּקוֹם אֲשֶׁר-יִבְחַר בְּאַחַד שְׁעָרֶיךָ--בַּטּוֹב לוֹ; לֹא, תּוֹנֶנּוּ. {ס}	17 he shall dwell with thee, in the midst of thee, in the place which he shall choose within one of thy gates, where it liketh him best; thou shalt not wrong him. {S}

Yet the Torah allows for slavery, and legislates it! If this person sold himself into slavery, or was rightfully purchased from another, how can you not stand up for what is legal?

Indeed, in the same parsha, in the previous perek, in another context, we have {Devarim 22}:

א לֹא-תִרְאֶה אֶת-שׁוֹר אָחִיךָ אוֹ אֶת-שֵׂיוֹ, נִדָּחִים, וְהִתְעַלַּמְתָּ, מֵהֶם: הָשֵׁב תְּשִׁיבֵם, לְאָחִיךָ.	1 Thou shalt not see thy brother's ox or his sheep driven away, and hide thyself from them; thou shalt surely bring them back unto thy brother.
ב וְאִם-לֹא קָרוֹב אָחִיךָ אֵלֶיךָ, וְלֹא יְדַעְתּוֹ--וַאֲסַפְתּוֹ, אֶל-תּוֹךְ בֵּיתֶךָ, וְהָיָה עִמְּךָ עַד דְּרֹשׁ אָחִיךָ אֹתוֹ, וַהֲשֵׁבֹתוֹ לוֹ.	2 And if thy brother be not nigh unto thee, and thou know him not, then thou shalt bring it home to thy house, and it shall be with thee until thy brother require it, and thou shalt restore it to him.
ג וְכֵן תַּעֲשֶׂה לַחֲמֹרוֹ, וְכֵן תַּעֲשֶׂה לְשִׂמְלָתוֹ, וְכֵן תַּעֲשֶׂה לְכָל-אֲבֵדַת אָחִיךָ אֲשֶׁר-תֹּאבַד מִמֶּנּוּ, וּמְצָאתָהּ: לֹא תוּכַל, לְהִתְעַלֵּם. {ס}	3 And so shalt thou do with his ass; and so shalt thou do with his garment; and so shalt thou do with every lost thing of thy brother's, which he hath lost, and thou hast found; thou mayest not hide thyself. {S}

If you have a legal obligation to return your fellow's lost object, not to take it for yourself and not to just leave it alone, how can the Torah in the next perek instruct you not only to not return his runaway slave, and indeed to help the runaway slave stay away and start a new life?

The answer is obvious, but asking the questions helps clarify it. Whatever the Torah's general perspective on slavery (in in general it stands in with reforms to standardize fair treatment of servants), there is law and then there is what is morally right. And regardless of the statutes about property, we are talking about a vulnerable human being here, looking to improve his own life and to escape a life of servitude. As we say elsewhere in the parsha, remember your own national history in Egypt. Of course you don't betray him and give him over to his master. To do so would be evil, rather than legal, and the law recognizes this. You shall not wrong him.